[net-next-2.6.git] / net / ipv6 / tunnel6.c

/*
 * 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Authors	Mitsuru KANDA  <mk@linux-ipv6.org>
 * 		YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
 */

#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)) {
		printk(KERN_ERR "tunnel6 init(): can't add protocol\n");
		return -EAGAIN;
	}
	if (inet6_add_protocol(&tunnel46_protocol, IPPROTO_IPIP)) {
		printk(KERN_ERR "tunnel6 init(): can't add protocol\n");
		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))
		printk(KERN_ERR "tunnel6 close: can't remove protocol\n");
	if (inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6))
		printk(KERN_ERR "tunnel6 close: can't remove protocol\n");
}

module_init(tunnel6_init);
module_exit(tunnel6_fini);
MODULE_LICENSE("GPL");
Commit	Line	Data
d2acc347 HX	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
50fba2aa	22	#include <linux/icmpv6.h>
d2acc347 HX	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>
5a0e3ad6	28	#include <linux/slab.h>
50fba2aa	29	#include <net/ipv6.h>
d2acc347 HX	30	#include <net/protocol.h>
	31	#include <net/xfrm.h>
	32
6f0bcf15 ED	33	static struct xfrm6_tunnel __rcu *tunnel6_handlers __read_mostly;
6f0bcf15 ED	34	static struct xfrm6_tunnel __rcu *tunnel46_handlers __read_mostly;
d2acc347 HX	35	static DEFINE_MUTEX(tunnel6_mutex);
d2acc347 HX	36
73d605d1	37	int xfrm6_tunnel_register(struct xfrm6_tunnel *handler, unsigned short family)
d2acc347	38	{
6f0bcf15 ED	39	struct xfrm6_tunnel __rcu **pprev;
6f0bcf15 ED	40	struct xfrm6_tunnel *t;
d2acc347 HX	41	int ret = -EEXIST;
	42	int priority = handler->priority;
	43
	44	mutex_lock(&tunnel6_mutex);
	45
73d605d1	46	for (pprev = (family == AF_INET6) ? &tunnel6_handlers : &tunnel46_handlers;
6f0bcf15 ED	47	(t = rcu_dereference_protected(*pprev,
	48	lockdep_is_held(&tunnel6_mutex))) != NULL;
	49	pprev = &t->next) {
	50	if (t->priority > priority)
d2acc347	51	break;
6f0bcf15	52	if (t->priority == priority)
d2acc347 HX	53	goto err;
	54	}
	55
	56	handler->next = *pprev;
49d61e23	57	rcu_assign_pointer(*pprev, handler);
d2acc347 HX	58
	59	ret = 0;
	60
	61	err:
	62	mutex_unlock(&tunnel6_mutex);
	63
	64	return ret;
	65	}
	66
	67	EXPORT_SYMBOL(xfrm6_tunnel_register);
	68
73d605d1	69	int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler, unsigned short family)
d2acc347	70	{
6f0bcf15 ED	71	struct xfrm6_tunnel __rcu **pprev;
6f0bcf15 ED	72	struct xfrm6_tunnel *t;
d2acc347 HX	73	int ret = -ENOENT;
	74
	75	mutex_lock(&tunnel6_mutex);
	76
73d605d1	77	for (pprev = (family == AF_INET6) ? &tunnel6_handlers : &tunnel46_handlers;
6f0bcf15 ED	78	(t = rcu_dereference_protected(*pprev,
	79	lockdep_is_held(&tunnel6_mutex))) != NULL;
	80	pprev = &t->next) {
	81	if (t == handler) {
d2acc347 HX	82	*pprev = handler->next;
	83	ret = 0;
	84	break;
	85	}
	86	}
	87
	88	mutex_unlock(&tunnel6_mutex);
	89
	90	synchronize_net();
	91
	92	return ret;
	93	}
	94
	95	EXPORT_SYMBOL(xfrm6_tunnel_deregister);
	96
875168a9 ED	97	#define for_each_tunnel_rcu(head, handler) \
	98	for (handler = rcu_dereference(head); \
	99	handler != NULL; \
	100	handler = rcu_dereference(handler->next)) \
	101
e5bbef20	102	static int tunnel6_rcv(struct sk_buff *skb)
d2acc347	103	{
d2acc347 HX	104	struct xfrm6_tunnel *handler;
d2acc347 HX	105
50fba2aa HX	106	if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
	107	goto drop;
	108
875168a9	109	for_each_tunnel_rcu(tunnel6_handlers, handler)
d2acc347 HX	110	if (!handler->handler(skb))
	111	return 0;
	112
3ffe533c	113	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
50fba2aa HX	114
50fba2aa HX	115	drop:
d2acc347 HX	116	kfree_skb(skb);
	117	return 0;
	118	}
	119
e5bbef20	120	static int tunnel46_rcv(struct sk_buff *skb)
73d605d1	121	{
73d605d1 KM	122	struct xfrm6_tunnel *handler;
73d605d1 KM	123
82836372	124	if (!pskb_may_pull(skb, sizeof(struct iphdr)))
73d605d1 KM	125	goto drop;
73d605d1 KM	126
875168a9	127	for_each_tunnel_rcu(tunnel46_handlers, handler)
73d605d1 KM	128	if (!handler->handler(skb))
	129	return 0;
	130
3ffe533c	131	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
73d605d1 KM	132
	133	drop:
	134	kfree_skb(skb);
	135	return 0;
	136	}
	137
d2acc347	138	static void tunnel6_err(struct sk_buff skb, struct inet6_skb_parm opt,
d5fdd6ba	139	u8 type, u8 code, int offset, __be32 info)
d2acc347 HX	140	{
	141	struct xfrm6_tunnel *handler;
	142
875168a9	143	for_each_tunnel_rcu(tunnel6_handlers, handler)
d2acc347 HX	144	if (!handler->err_handler(skb, opt, type, code, offset, info))
	145	break;
	146	}
	147
41135cc8	148	static const struct inet6_protocol tunnel6_protocol = {
d2acc347 HX	149	.handler = tunnel6_rcv,
	150	.err_handler = tunnel6_err,
	151	.flags = INET6_PROTO_NOPOLICY\|INET6_PROTO_FINAL,
	152	};
	153
41135cc8	154	static const struct inet6_protocol tunnel46_protocol = {
73d605d1 KM	155	.handler = tunnel46_rcv,
	156	.err_handler = tunnel6_err,
	157	.flags = INET6_PROTO_NOPOLICY\|INET6_PROTO_FINAL,
	158	};
	159
d2acc347 HX	160	static int __init tunnel6_init(void)
	161	{
	162	if (inet6_add_protocol(&tunnel6_protocol, IPPROTO_IPV6)) {
	163	printk(KERN_ERR "tunnel6 init(): can't add protocol\n");
	164	return -EAGAIN;
	165	}
73d605d1 KM	166	if (inet6_add_protocol(&tunnel46_protocol, IPPROTO_IPIP)) {
	167	printk(KERN_ERR "tunnel6 init(): can't add protocol\n");
	168	inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6);
	169	return -EAGAIN;
	170	}
d2acc347 HX	171	return 0;
	172	}
	173
	174	static void __exit tunnel6_fini(void)
	175	{
73d605d1 KM	176	if (inet6_del_protocol(&tunnel46_protocol, IPPROTO_IPIP))
73d605d1 KM	177	printk(KERN_ERR "tunnel6 close: can't remove protocol\n");
d2acc347 HX	178	if (inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6))
	179	printk(KERN_ERR "tunnel6 close: can't remove protocol\n");
	180	}
	181
	182	module_init(tunnel6_init);
	183	module_exit(tunnel6_fini);
	184	MODULE_LICENSE("GPL");