[mirror_ubuntu-bionic-kernel.git] / net / ipv6 / xfrm6_tunnel.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, see <http://www.gnu.org/licenses/>.
 *
 * Authors	Mitsuru KANDA  <mk@linux-ipv6.org>
 *		YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
 *
 * Based on net/ipv4/xfrm4_tunnel.c
 *
 */
#include <linux/module.h>
#include <linux/xfrm.h>
#include <linux/slab.h>
#include <linux/rculist.h>
#include <net/ip.h>
#include <net/xfrm.h>
#include <net/ipv6.h>
#include <linux/ipv6.h>
#include <linux/icmpv6.h>
#include <linux/mutex.h>
#include <net/netns/generic.h>

#define XFRM6_TUNNEL_SPI_BYADDR_HSIZE 256
#define XFRM6_TUNNEL_SPI_BYSPI_HSIZE 256

#define XFRM6_TUNNEL_SPI_MIN	1
#define XFRM6_TUNNEL_SPI_MAX	0xffffffff

struct xfrm6_tunnel_net {
	struct hlist_head spi_byaddr[XFRM6_TUNNEL_SPI_BYADDR_HSIZE];
	struct hlist_head spi_byspi[XFRM6_TUNNEL_SPI_BYSPI_HSIZE];
	u32 spi;
};

static int xfrm6_tunnel_net_id __read_mostly;
static inline struct xfrm6_tunnel_net *xfrm6_tunnel_pernet(struct net *net)
{
	return net_generic(net, xfrm6_tunnel_net_id);
}

/*
 * xfrm_tunnel_spi things are for allocating unique id ("spi")
 * per xfrm_address_t.
 */
struct xfrm6_tunnel_spi {
	struct hlist_node	list_byaddr;
	struct hlist_node	list_byspi;
	xfrm_address_t		addr;
	u32			spi;
	atomic_t		refcnt;
	struct rcu_head		rcu_head;
};

static DEFINE_SPINLOCK(xfrm6_tunnel_spi_lock);

static struct kmem_cache *xfrm6_tunnel_spi_kmem __read_mostly;

static inline unsigned int xfrm6_tunnel_spi_hash_byaddr(const xfrm_address_t *addr)
{
	unsigned int h;

	h = ipv6_addr_hash((const struct in6_addr *)addr);
	h ^= h >> 16;
	h ^= h >> 8;
	h &= XFRM6_TUNNEL_SPI_BYADDR_HSIZE - 1;

	return h;
}

static inline unsigned int xfrm6_tunnel_spi_hash_byspi(u32 spi)
{
	return spi % XFRM6_TUNNEL_SPI_BYSPI_HSIZE;
}

static struct xfrm6_tunnel_spi *__xfrm6_tunnel_spi_lookup(struct net *net, const xfrm_address_t *saddr)
{
	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
	struct xfrm6_tunnel_spi *x6spi;

	hlist_for_each_entry_rcu(x6spi,
			     &xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
			     list_byaddr) {
		if (xfrm6_addr_equal(&x6spi->addr, saddr))
			return x6spi;
	}

	return NULL;
}

__be32 xfrm6_tunnel_spi_lookup(struct net *net, const xfrm_address_t *saddr)
{
	struct xfrm6_tunnel_spi *x6spi;
	u32 spi;

	rcu_read_lock_bh();
	x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
	spi = x6spi ? x6spi->spi : 0;
	rcu_read_unlock_bh();
	return htonl(spi);
}
EXPORT_SYMBOL(xfrm6_tunnel_spi_lookup);

static int __xfrm6_tunnel_spi_check(struct net *net, u32 spi)
{
	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
	struct xfrm6_tunnel_spi *x6spi;
	int index = xfrm6_tunnel_spi_hash_byspi(spi);

	hlist_for_each_entry(x6spi,
			     &xfrm6_tn->spi_byspi[index],
			     list_byspi) {
		if (x6spi->spi == spi)
			return -1;
	}
	return index;
}

static u32 __xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr)
{
	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
	u32 spi;
	struct xfrm6_tunnel_spi *x6spi;
	int index;

	if (xfrm6_tn->spi < XFRM6_TUNNEL_SPI_MIN ||
	    xfrm6_tn->spi >= XFRM6_TUNNEL_SPI_MAX)
		xfrm6_tn->spi = XFRM6_TUNNEL_SPI_MIN;
	else
		xfrm6_tn->spi++;

	for (spi = xfrm6_tn->spi; spi <= XFRM6_TUNNEL_SPI_MAX; spi++) {
		index = __xfrm6_tunnel_spi_check(net, spi);
		if (index >= 0)
			goto alloc_spi;
	}
	for (spi = XFRM6_TUNNEL_SPI_MIN; spi < xfrm6_tn->spi; spi++) {
		index = __xfrm6_tunnel_spi_check(net, spi);
		if (index >= 0)
			goto alloc_spi;
	}
	spi = 0;
	goto out;
alloc_spi:
	xfrm6_tn->spi = spi;
	x6spi = kmem_cache_alloc(xfrm6_tunnel_spi_kmem, GFP_ATOMIC);
	if (!x6spi)
		goto out;

	memcpy(&x6spi->addr, saddr, sizeof(x6spi->addr));
	x6spi->spi = spi;
	atomic_set(&x6spi->refcnt, 1);

	hlist_add_head_rcu(&x6spi->list_byspi, &xfrm6_tn->spi_byspi[index]);

	index = xfrm6_tunnel_spi_hash_byaddr(saddr);
	hlist_add_head_rcu(&x6spi->list_byaddr, &xfrm6_tn->spi_byaddr[index]);
out:
	return spi;
}

__be32 xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr)
{
	struct xfrm6_tunnel_spi *x6spi;
	u32 spi;

	spin_lock_bh(&xfrm6_tunnel_spi_lock);
	x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
	if (x6spi) {
		atomic_inc(&x6spi->refcnt);
		spi = x6spi->spi;
	} else
		spi = __xfrm6_tunnel_alloc_spi(net, saddr);
	spin_unlock_bh(&xfrm6_tunnel_spi_lock);

	return htonl(spi);
}
EXPORT_SYMBOL(xfrm6_tunnel_alloc_spi);

static void x6spi_destroy_rcu(struct rcu_head *head)
{
	kmem_cache_free(xfrm6_tunnel_spi_kmem,
			container_of(head, struct xfrm6_tunnel_spi, rcu_head));
}

static void xfrm6_tunnel_free_spi(struct net *net, xfrm_address_t *saddr)
{
	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
	struct xfrm6_tunnel_spi *x6spi;
	struct hlist_node *n;

	spin_lock_bh(&xfrm6_tunnel_spi_lock);

	hlist_for_each_entry_safe(x6spi, n,
				  &xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
				  list_byaddr)
	{
		if (xfrm6_addr_equal(&x6spi->addr, saddr)) {
			if (atomic_dec_and_test(&x6spi->refcnt)) {
				hlist_del_rcu(&x6spi->list_byaddr);
				hlist_del_rcu(&x6spi->list_byspi);
				call_rcu(&x6spi->rcu_head, x6spi_destroy_rcu);
				break;
			}
		}
	}
	spin_unlock_bh(&xfrm6_tunnel_spi_lock);
}

static int xfrm6_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
{
	skb_push(skb, -skb_network_offset(skb));
	return 0;
}

static int xfrm6_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
{
	return skb_network_header(skb)[IP6CB(skb)->nhoff];
}

static int xfrm6_tunnel_rcv(struct sk_buff *skb)
{
	struct net *net = dev_net(skb->dev);
	const struct ipv6hdr *iph = ipv6_hdr(skb);
	__be32 spi;

	spi = xfrm6_tunnel_spi_lookup(net, (const xfrm_address_t *)&iph->saddr);
	return xfrm6_rcv_spi(skb, IPPROTO_IPV6, spi);
}

static int xfrm6_tunnel_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
			    u8 type, u8 code, int offset, __be32 info)
{
	/* xfrm6_tunnel native err handling */
	switch (type) {
	case ICMPV6_DEST_UNREACH:
		switch (code) {
		case ICMPV6_NOROUTE:
		case ICMPV6_ADM_PROHIBITED:
		case ICMPV6_NOT_NEIGHBOUR:
		case ICMPV6_ADDR_UNREACH:
		case ICMPV6_PORT_UNREACH:
		default:
			break;
		}
		break;
	case ICMPV6_PKT_TOOBIG:
		break;
	case ICMPV6_TIME_EXCEED:
		switch (code) {
		case ICMPV6_EXC_HOPLIMIT:
			break;
		case ICMPV6_EXC_FRAGTIME:
		default:
			break;
		}
		break;
	case ICMPV6_PARAMPROB:
		switch (code) {
		case ICMPV6_HDR_FIELD: break;
		case ICMPV6_UNK_NEXTHDR: break;
		case ICMPV6_UNK_OPTION: break;
		}
		break;
	default:
		break;
	}

	return 0;
}

static int xfrm6_tunnel_init_state(struct xfrm_state *x)
{
	if (x->props.mode != XFRM_MODE_TUNNEL)
		return -EINVAL;

	if (x->encap)
		return -EINVAL;

	x->props.header_len = sizeof(struct ipv6hdr);

	return 0;
}

static void xfrm6_tunnel_destroy(struct xfrm_state *x)
{
	struct net *net = xs_net(x);

	xfrm6_tunnel_free_spi(net, (xfrm_address_t *)&x->props.saddr);
}

static const struct xfrm_type xfrm6_tunnel_type = {
	.description	= "IP6IP6",
	.owner          = THIS_MODULE,
	.proto		= IPPROTO_IPV6,
	.init_state	= xfrm6_tunnel_init_state,
	.destructor	= xfrm6_tunnel_destroy,
	.input		= xfrm6_tunnel_input,
	.output		= xfrm6_tunnel_output,
};

static struct xfrm6_tunnel xfrm6_tunnel_handler __read_mostly = {
	.handler	= xfrm6_tunnel_rcv,
	.err_handler	= xfrm6_tunnel_err,
	.priority	= 2,
};

static struct xfrm6_tunnel xfrm46_tunnel_handler __read_mostly = {
	.handler	= xfrm6_tunnel_rcv,
	.err_handler	= xfrm6_tunnel_err,
	.priority	= 2,
};

static int __net_init xfrm6_tunnel_net_init(struct net *net)
{
	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
	unsigned int i;

	for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++)
		INIT_HLIST_HEAD(&xfrm6_tn->spi_byaddr[i]);
	for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++)
		INIT_HLIST_HEAD(&xfrm6_tn->spi_byspi[i]);
	xfrm6_tn->spi = 0;

	return 0;
}

static void __net_exit xfrm6_tunnel_net_exit(struct net *net)
{
}

static struct pernet_operations xfrm6_tunnel_net_ops = {
	.init	= xfrm6_tunnel_net_init,
	.exit	= xfrm6_tunnel_net_exit,
	.id	= &xfrm6_tunnel_net_id,
	.size	= sizeof(struct xfrm6_tunnel_net),
};

static int __init xfrm6_tunnel_init(void)
{
	int rv;

	xfrm6_tunnel_spi_kmem = kmem_cache_create("xfrm6_tunnel_spi",
						  sizeof(struct xfrm6_tunnel_spi),
						  0, SLAB_HWCACHE_ALIGN,
						  NULL);
	if (!xfrm6_tunnel_spi_kmem)
		return -ENOMEM;
	rv = register_pernet_subsys(&xfrm6_tunnel_net_ops);
	if (rv < 0)
		goto out_pernet;
	rv = xfrm_register_type(&xfrm6_tunnel_type, AF_INET6);
	if (rv < 0)
		goto out_type;
	rv = xfrm6_tunnel_register(&xfrm6_tunnel_handler, AF_INET6);
	if (rv < 0)
		goto out_xfrm6;
	rv = xfrm6_tunnel_register(&xfrm46_tunnel_handler, AF_INET);
	if (rv < 0)
		goto out_xfrm46;
	return 0;

out_xfrm46:
	xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
out_xfrm6:
	xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
out_type:
	unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
out_pernet:
	kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
	return rv;
}

static void __exit xfrm6_tunnel_fini(void)
{
	xfrm6_tunnel_deregister(&xfrm46_tunnel_handler, AF_INET);
	xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
	xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
	unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
	kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
}

module_init(xfrm6_tunnel_init);
module_exit(xfrm6_tunnel_fini);
MODULE_LICENSE("GPL");
MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_IPV6);
Commit	Line	Data
	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, see <http://www.gnu.org/licenses/>.
	16	*
	17	* Authors Mitsuru KANDA <mk@linux-ipv6.org>
	18	* YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
	19	*
	20	* Based on net/ipv4/xfrm4_tunnel.c
	21	*
	22	*/
	23	#include <linux/module.h>
	24	#include <linux/xfrm.h>
	25	#include <linux/slab.h>
	26	#include <linux/rculist.h>
	27	#include <net/ip.h>
	28	#include <net/xfrm.h>
	29	#include <net/ipv6.h>
	30	#include <linux/ipv6.h>
	31	#include <linux/icmpv6.h>
	32	#include <linux/mutex.h>
	33	#include <net/netns/generic.h>
	34
	35	#define XFRM6_TUNNEL_SPI_BYADDR_HSIZE 256
	36	#define XFRM6_TUNNEL_SPI_BYSPI_HSIZE 256
	37
	38	#define XFRM6_TUNNEL_SPI_MIN 1
	39	#define XFRM6_TUNNEL_SPI_MAX 0xffffffff
	40
	41	struct xfrm6_tunnel_net {
	42	struct hlist_head spi_byaddr[XFRM6_TUNNEL_SPI_BYADDR_HSIZE];
	43	struct hlist_head spi_byspi[XFRM6_TUNNEL_SPI_BYSPI_HSIZE];
	44	u32 spi;
	45	};
	46
	47	static int xfrm6_tunnel_net_id __read_mostly;
	48	static inline struct xfrm6_tunnel_net xfrm6_tunnel_pernet(struct net net)
	49	{
	50	return net_generic(net, xfrm6_tunnel_net_id);
	51	}
	52
	53	/*
	54	* xfrm_tunnel_spi things are for allocating unique id ("spi")
	55	* per xfrm_address_t.
	56	*/
	57	struct xfrm6_tunnel_spi {
	58	struct hlist_node list_byaddr;
	59	struct hlist_node list_byspi;
	60	xfrm_address_t addr;
	61	u32 spi;
	62	atomic_t refcnt;
	63	struct rcu_head rcu_head;
	64	};
	65
	66	static DEFINE_SPINLOCK(xfrm6_tunnel_spi_lock);
	67
	68	static struct kmem_cache *xfrm6_tunnel_spi_kmem __read_mostly;
	69
	70	static inline unsigned int xfrm6_tunnel_spi_hash_byaddr(const xfrm_address_t *addr)
	71	{
	72	unsigned int h;
	73
	74	h = ipv6_addr_hash((const struct in6_addr *)addr);
	75	h ^= h >> 16;
	76	h ^= h >> 8;
	77	h &= XFRM6_TUNNEL_SPI_BYADDR_HSIZE - 1;
	78
	79	return h;
	80	}
	81
	82	static inline unsigned int xfrm6_tunnel_spi_hash_byspi(u32 spi)
	83	{
	84	return spi % XFRM6_TUNNEL_SPI_BYSPI_HSIZE;
	85	}
	86
	87	static struct xfrm6_tunnel_spi __xfrm6_tunnel_spi_lookup(struct net net, const xfrm_address_t *saddr)
	88	{
	89	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
	90	struct xfrm6_tunnel_spi *x6spi;
	91
	92	hlist_for_each_entry_rcu(x6spi,
	93	&xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
	94	list_byaddr) {
	95	if (xfrm6_addr_equal(&x6spi->addr, saddr))
	96	return x6spi;
	97	}
	98
	99	return NULL;
	100	}
	101
	102	__be32 xfrm6_tunnel_spi_lookup(struct net net, const xfrm_address_t saddr)
	103	{
	104	struct xfrm6_tunnel_spi *x6spi;
	105	u32 spi;
	106
	107	rcu_read_lock_bh();
	108	x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
	109	spi = x6spi ? x6spi->spi : 0;
	110	rcu_read_unlock_bh();
	111	return htonl(spi);
	112	}
	113	EXPORT_SYMBOL(xfrm6_tunnel_spi_lookup);
	114
	115	static int __xfrm6_tunnel_spi_check(struct net *net, u32 spi)
	116	{
	117	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
	118	struct xfrm6_tunnel_spi *x6spi;
	119	int index = xfrm6_tunnel_spi_hash_byspi(spi);
	120
	121	hlist_for_each_entry(x6spi,
	122	&xfrm6_tn->spi_byspi[index],
	123	list_byspi) {
	124	if (x6spi->spi == spi)
	125	return -1;
	126	}
	127	return index;
	128	}
	129
	130	static u32 __xfrm6_tunnel_alloc_spi(struct net net, xfrm_address_t saddr)
	131	{
	132	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
	133	u32 spi;
	134	struct xfrm6_tunnel_spi *x6spi;
	135	int index;
	136
	137	if (xfrm6_tn->spi < XFRM6_TUNNEL_SPI_MIN \|\|
	138	xfrm6_tn->spi >= XFRM6_TUNNEL_SPI_MAX)
	139	xfrm6_tn->spi = XFRM6_TUNNEL_SPI_MIN;
	140	else
	141	xfrm6_tn->spi++;
	142
	143	for (spi = xfrm6_tn->spi; spi <= XFRM6_TUNNEL_SPI_MAX; spi++) {
	144	index = __xfrm6_tunnel_spi_check(net, spi);
	145	if (index >= 0)
	146	goto alloc_spi;
	147	}
	148	for (spi = XFRM6_TUNNEL_SPI_MIN; spi < xfrm6_tn->spi; spi++) {
	149	index = __xfrm6_tunnel_spi_check(net, spi);
	150	if (index >= 0)
	151	goto alloc_spi;
	152	}
	153	spi = 0;
	154	goto out;
	155	alloc_spi:
	156	xfrm6_tn->spi = spi;
	157	x6spi = kmem_cache_alloc(xfrm6_tunnel_spi_kmem, GFP_ATOMIC);
	158	if (!x6spi)
	159	goto out;
	160
	161	memcpy(&x6spi->addr, saddr, sizeof(x6spi->addr));
	162	x6spi->spi = spi;
	163	atomic_set(&x6spi->refcnt, 1);
	164
	165	hlist_add_head_rcu(&x6spi->list_byspi, &xfrm6_tn->spi_byspi[index]);
	166
	167	index = xfrm6_tunnel_spi_hash_byaddr(saddr);
	168	hlist_add_head_rcu(&x6spi->list_byaddr, &xfrm6_tn->spi_byaddr[index]);
	169	out:
	170	return spi;
	171	}
	172
	173	__be32 xfrm6_tunnel_alloc_spi(struct net net, xfrm_address_t saddr)
	174	{
	175	struct xfrm6_tunnel_spi *x6spi;
	176	u32 spi;
	177
	178	spin_lock_bh(&xfrm6_tunnel_spi_lock);
	179	x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
	180	if (x6spi) {
	181	atomic_inc(&x6spi->refcnt);
	182	spi = x6spi->spi;
	183	} else
	184	spi = __xfrm6_tunnel_alloc_spi(net, saddr);
	185	spin_unlock_bh(&xfrm6_tunnel_spi_lock);
	186
	187	return htonl(spi);
	188	}
	189	EXPORT_SYMBOL(xfrm6_tunnel_alloc_spi);
	190
	191	static void x6spi_destroy_rcu(struct rcu_head *head)
	192	{
	193	kmem_cache_free(xfrm6_tunnel_spi_kmem,
	194	container_of(head, struct xfrm6_tunnel_spi, rcu_head));
	195	}
	196
	197	static void xfrm6_tunnel_free_spi(struct net net, xfrm_address_t saddr)
	198	{
	199	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
	200	struct xfrm6_tunnel_spi *x6spi;
	201	struct hlist_node *n;
	202
	203	spin_lock_bh(&xfrm6_tunnel_spi_lock);
	204
	205	hlist_for_each_entry_safe(x6spi, n,
	206	&xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
	207	list_byaddr)
	208	{
	209	if (xfrm6_addr_equal(&x6spi->addr, saddr)) {
	210	if (atomic_dec_and_test(&x6spi->refcnt)) {
	211	hlist_del_rcu(&x6spi->list_byaddr);
	212	hlist_del_rcu(&x6spi->list_byspi);
	213	call_rcu(&x6spi->rcu_head, x6spi_destroy_rcu);
	214	break;
	215	}
	216	}
	217	}
	218	spin_unlock_bh(&xfrm6_tunnel_spi_lock);
	219	}
	220
	221	static int xfrm6_tunnel_output(struct xfrm_state x, struct sk_buff skb)
	222	{
	223	skb_push(skb, -skb_network_offset(skb));
	224	return 0;
	225	}
	226
	227	static int xfrm6_tunnel_input(struct xfrm_state x, struct sk_buff skb)
	228	{
	229	return skb_network_header(skb)[IP6CB(skb)->nhoff];
	230	}
	231
	232	static int xfrm6_tunnel_rcv(struct sk_buff *skb)
	233	{
	234	struct net *net = dev_net(skb->dev);
	235	const struct ipv6hdr *iph = ipv6_hdr(skb);
	236	__be32 spi;
	237
	238	spi = xfrm6_tunnel_spi_lookup(net, (const xfrm_address_t *)&iph->saddr);
	239	return xfrm6_rcv_spi(skb, IPPROTO_IPV6, spi);
	240	}
	241
	242	static int xfrm6_tunnel_err(struct sk_buff skb, struct inet6_skb_parm opt,
	243	u8 type, u8 code, int offset, __be32 info)
	244	{
	245	/* xfrm6_tunnel native err handling */
	246	switch (type) {
	247	case ICMPV6_DEST_UNREACH:
	248	switch (code) {
	249	case ICMPV6_NOROUTE:
	250	case ICMPV6_ADM_PROHIBITED:
	251	case ICMPV6_NOT_NEIGHBOUR:
	252	case ICMPV6_ADDR_UNREACH:
	253	case ICMPV6_PORT_UNREACH:
	254	default:
	255	break;
	256	}
	257	break;
	258	case ICMPV6_PKT_TOOBIG:
	259	break;
	260	case ICMPV6_TIME_EXCEED:
	261	switch (code) {
	262	case ICMPV6_EXC_HOPLIMIT:
	263	break;
	264	case ICMPV6_EXC_FRAGTIME:
	265	default:
	266	break;
	267	}
	268	break;
	269	case ICMPV6_PARAMPROB:
	270	switch (code) {
	271	case ICMPV6_HDR_FIELD: break;
	272	case ICMPV6_UNK_NEXTHDR: break;
	273	case ICMPV6_UNK_OPTION: break;
	274	}
	275	break;
	276	default:
	277	break;
	278	}
	279
	280	return 0;
	281	}
	282
	283	static int xfrm6_tunnel_init_state(struct xfrm_state *x)
	284	{
	285	if (x->props.mode != XFRM_MODE_TUNNEL)
	286	return -EINVAL;
	287
	288	if (x->encap)
	289	return -EINVAL;
	290
	291	x->props.header_len = sizeof(struct ipv6hdr);
	292
	293	return 0;
	294	}
	295
	296	static void xfrm6_tunnel_destroy(struct xfrm_state *x)
	297	{
	298	struct net *net = xs_net(x);
	299
	300	xfrm6_tunnel_free_spi(net, (xfrm_address_t *)&x->props.saddr);
	301	}
	302
	303	static const struct xfrm_type xfrm6_tunnel_type = {
	304	.description = "IP6IP6",
	305	.owner = THIS_MODULE,
	306	.proto = IPPROTO_IPV6,
	307	.init_state = xfrm6_tunnel_init_state,
	308	.destructor = xfrm6_tunnel_destroy,
	309	.input = xfrm6_tunnel_input,
	310	.output = xfrm6_tunnel_output,
	311	};
	312
	313	static struct xfrm6_tunnel xfrm6_tunnel_handler __read_mostly = {
	314	.handler = xfrm6_tunnel_rcv,
	315	.err_handler = xfrm6_tunnel_err,
	316	.priority = 2,
	317	};
	318
	319	static struct xfrm6_tunnel xfrm46_tunnel_handler __read_mostly = {
	320	.handler = xfrm6_tunnel_rcv,
	321	.err_handler = xfrm6_tunnel_err,
	322	.priority = 2,
	323	};
	324
	325	static int __net_init xfrm6_tunnel_net_init(struct net *net)
	326	{
	327	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
	328	unsigned int i;
	329
	330	for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++)
	331	INIT_HLIST_HEAD(&xfrm6_tn->spi_byaddr[i]);
	332	for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++)
	333	INIT_HLIST_HEAD(&xfrm6_tn->spi_byspi[i]);
	334	xfrm6_tn->spi = 0;
	335
	336	return 0;
	337	}
	338
	339	static void __net_exit xfrm6_tunnel_net_exit(struct net *net)
	340	{
	341	}
	342
	343	static struct pernet_operations xfrm6_tunnel_net_ops = {
	344	.init = xfrm6_tunnel_net_init,
	345	.exit = xfrm6_tunnel_net_exit,
	346	.id = &xfrm6_tunnel_net_id,
	347	.size = sizeof(struct xfrm6_tunnel_net),
	348	};
	349
	350	static int __init xfrm6_tunnel_init(void)
	351	{
	352	int rv;
	353
	354	xfrm6_tunnel_spi_kmem = kmem_cache_create("xfrm6_tunnel_spi",
	355	sizeof(struct xfrm6_tunnel_spi),
	356	0, SLAB_HWCACHE_ALIGN,
	357	NULL);
	358	if (!xfrm6_tunnel_spi_kmem)
	359	return -ENOMEM;
	360	rv = register_pernet_subsys(&xfrm6_tunnel_net_ops);
	361	if (rv < 0)
	362	goto out_pernet;
	363	rv = xfrm_register_type(&xfrm6_tunnel_type, AF_INET6);
	364	if (rv < 0)
	365	goto out_type;
	366	rv = xfrm6_tunnel_register(&xfrm6_tunnel_handler, AF_INET6);
	367	if (rv < 0)
	368	goto out_xfrm6;
	369	rv = xfrm6_tunnel_register(&xfrm46_tunnel_handler, AF_INET);
	370	if (rv < 0)
	371	goto out_xfrm46;
	372	return 0;
	373
	374	out_xfrm46:
	375	xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
	376	out_xfrm6:
	377	xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
	378	out_type:
	379	unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
	380	out_pernet:
	381	kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
	382	return rv;
	383	}
	384
	385	static void __exit xfrm6_tunnel_fini(void)
	386	{
	387	xfrm6_tunnel_deregister(&xfrm46_tunnel_handler, AF_INET);
	388	xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
	389	xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
	390	unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
	391	kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
	392	}
	393
	394	module_init(xfrm6_tunnel_init);
	395	module_exit(xfrm6_tunnel_fini);
	396	MODULE_LICENSE("GPL");
	397	MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_IPV6);