[linux-block.git] / net / ipv6 / xfrm6_tunnel.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C)2003,2004 USAGI/WIDE Project
 *
 * 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 unsigned 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;
	refcount_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, lockdep_is_held(&xfrm6_tunnel_spi_lock)) {
		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;

		if (spi == XFRM6_TUNNEL_SPI_MAX)
			break;
	}
	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;
	refcount_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) {
		refcount_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 (refcount_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, NULL);
}

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, struct netlink_ext_ack *extack)
{
	if (x->props.mode != XFRM_MODE_TUNNEL) {
		NL_SET_ERR_MSG(extack, "IPv6 tunnel can only be used with tunnel mode");
		return -EINVAL;
	}

	if (x->encap) {
		NL_SET_ERR_MSG(extack, "IPv6 tunnel is not compatible with encapsulation");
		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 = {
	.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	= 3,
};

static struct xfrm6_tunnel xfrm46_tunnel_handler __read_mostly = {
	.handler	= xfrm6_tunnel_rcv,
	.err_handler	= xfrm6_tunnel_err,
	.priority	= 3,
};

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

	xfrm_flush_gc();
	xfrm_state_flush(net, 0, false, true);

	for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++)
		WARN_ON_ONCE(!hlist_empty(&xfrm6_tn->spi_byaddr[i]));

	for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++)
		WARN_ON_ONCE(!hlist_empty(&xfrm6_tn->spi_byspi[i]));
}

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);
	/* Someone maybe has gotten the xfrm6_tunnel_spi.
	 * So need to wait it.
	 */
	rcu_barrier();
	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
1ccea77e	1	// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4 LT	2	/*
	3	* Copyright (C)2003,2004 USAGI/WIDE Project
	4	*
1da177e4	5	* Authors Mitsuru KANDA <mk@linux-ipv6.org>
67ba4152	6	* YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
1da177e4 LT	7	*
1da177e4 LT	8	* Based on net/ipv4/xfrm4_tunnel.c
1da177e4	9	*/
1da177e4 LT	10	#include <linux/module.h>
1da177e4 LT	11	#include <linux/xfrm.h>
5a0e3ad6	12	#include <linux/slab.h>
91cc3bb0	13	#include <linux/rculist.h>
1da177e4 LT	14	#include <net/ip.h>
	15	#include <net/xfrm.h>
	16	#include <net/ipv6.h>
1da177e4 LT	17	#include <linux/ipv6.h>
1da177e4 LT	18	#include <linux/icmpv6.h>
4a3e2f71	19	#include <linux/mutex.h>
a1664773 AD	20	#include <net/netns/generic.h>
	21
	22	#define XFRM6_TUNNEL_SPI_BYADDR_HSIZE 256
	23	#define XFRM6_TUNNEL_SPI_BYSPI_HSIZE 256
	24
	25	#define XFRM6_TUNNEL_SPI_MIN 1
	26	#define XFRM6_TUNNEL_SPI_MAX 0xffffffff
	27
	28	struct xfrm6_tunnel_net {
	29	struct hlist_head spi_byaddr[XFRM6_TUNNEL_SPI_BYADDR_HSIZE];
	30	struct hlist_head spi_byspi[XFRM6_TUNNEL_SPI_BYSPI_HSIZE];
	31	u32 spi;
	32	};
	33
c7d03a00	34	static unsigned int xfrm6_tunnel_net_id __read_mostly;
a1664773 AD	35	static inline struct xfrm6_tunnel_net xfrm6_tunnel_pernet(struct net net)
	36	{
	37	return net_generic(net, xfrm6_tunnel_net_id);
	38	}
1da177e4	39
1da177e4	40	/*
1ab1457c	41	* xfrm_tunnel_spi things are for allocating unique id ("spi")
1da177e4 LT	42	* per xfrm_address_t.
	43	*/
	44	struct xfrm6_tunnel_spi {
91cc3bb0 ED	45	struct hlist_node list_byaddr;
	46	struct hlist_node list_byspi;
	47	xfrm_address_t addr;
	48	u32 spi;
d12f3827	49	refcount_t refcnt;
91cc3bb0	50	struct rcu_head rcu_head;
1da177e4 LT	51	};
1da177e4 LT	52
91cc3bb0	53	static DEFINE_SPINLOCK(xfrm6_tunnel_spi_lock);
1da177e4	54
e18b890b	55	static struct kmem_cache *xfrm6_tunnel_spi_kmem __read_mostly;
1da177e4	56
95c96174	57	static inline unsigned int xfrm6_tunnel_spi_hash_byaddr(const xfrm_address_t *addr)
1da177e4	58	{
95c96174	59	unsigned int h;
1da177e4	60
2b464f61	61	h = ipv6_addr_hash((const struct in6_addr *)addr);
1da177e4 LT	62	h ^= h >> 16;
	63	h ^= h >> 8;
	64	h &= XFRM6_TUNNEL_SPI_BYADDR_HSIZE - 1;
	65
1da177e4 LT	66	return h;
	67	}
	68
95c96174	69	static inline unsigned int xfrm6_tunnel_spi_hash_byspi(u32 spi)
1da177e4 LT	70	{
	71	return spi % XFRM6_TUNNEL_SPI_BYSPI_HSIZE;
	72	}
	73
b71d1d42	74	static struct xfrm6_tunnel_spi __xfrm6_tunnel_spi_lookup(struct net net, const xfrm_address_t *saddr)
1da177e4	75	{
a1664773	76	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
1da177e4	77	struct xfrm6_tunnel_spi *x6spi;
1da177e4	78
b67bfe0d	79	hlist_for_each_entry_rcu(x6spi,
a1664773	80	&xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
edf0d283	81	list_byaddr, lockdep_is_held(&xfrm6_tunnel_spi_lock)) {
ff88b30c	82	if (xfrm6_addr_equal(&x6spi->addr, saddr))
1da177e4	83	return x6spi;
1da177e4 LT	84	}
1da177e4 LT	85
1da177e4 LT	86	return NULL;
	87	}
	88
b71d1d42	89	__be32 xfrm6_tunnel_spi_lookup(struct net net, const xfrm_address_t saddr)
1da177e4 LT	90	{
	91	struct xfrm6_tunnel_spi *x6spi;
	92	u32 spi;
	93
91cc3bb0	94	rcu_read_lock_bh();
a1664773	95	x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
1da177e4	96	spi = x6spi ? x6spi->spi : 0;
91cc3bb0	97	rcu_read_unlock_bh();
5b122545	98	return htonl(spi);
1da177e4	99	}
1da177e4 LT	100	EXPORT_SYMBOL(xfrm6_tunnel_spi_lookup);
1da177e4 LT	101
a1664773	102	static int __xfrm6_tunnel_spi_check(struct net *net, u32 spi)
df8ea19b	103	{
a1664773	104	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
df8ea19b YH	105	struct xfrm6_tunnel_spi *x6spi;
df8ea19b YH	106	int index = xfrm6_tunnel_spi_hash_byspi(spi);
df8ea19b	107
b67bfe0d	108	hlist_for_each_entry(x6spi,
a1664773	109	&xfrm6_tn->spi_byspi[index],
df8ea19b YH	110	list_byspi) {
	111	if (x6spi->spi == spi)
	112	return -1;
	113	}
	114	return index;
	115	}
	116
a1664773	117	static u32 __xfrm6_tunnel_alloc_spi(struct net net, xfrm_address_t saddr)
1da177e4	118	{
a1664773	119	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
1da177e4 LT	120	u32 spi;
1da177e4 LT	121	struct xfrm6_tunnel_spi *x6spi;
df8ea19b	122	int index;
1da177e4	123
a1664773 AD	124	if (xfrm6_tn->spi < XFRM6_TUNNEL_SPI_MIN \|\|
	125	xfrm6_tn->spi >= XFRM6_TUNNEL_SPI_MAX)
	126	xfrm6_tn->spi = XFRM6_TUNNEL_SPI_MIN;
1da177e4	127	else
a1664773	128	xfrm6_tn->spi++;
1da177e4	129
a1664773 AD	130	for (spi = xfrm6_tn->spi; spi <= XFRM6_TUNNEL_SPI_MAX; spi++) {
a1664773 AD	131	index = __xfrm6_tunnel_spi_check(net, spi);
df8ea19b YH	132	if (index >= 0)
df8ea19b YH	133	goto alloc_spi;
fa89a459 Y	134
	135	if (spi == XFRM6_TUNNEL_SPI_MAX)
	136	break;
1da177e4	137	}
a1664773 AD	138	for (spi = XFRM6_TUNNEL_SPI_MIN; spi < xfrm6_tn->spi; spi++) {
a1664773 AD	139	index = __xfrm6_tunnel_spi_check(net, spi);
df8ea19b YH	140	if (index >= 0)
df8ea19b YH	141	goto alloc_spi;
1da177e4 LT	142	}
	143	spi = 0;
	144	goto out;
	145	alloc_spi:
a1664773	146	xfrm6_tn->spi = spi;
54e6ecb2	147	x6spi = kmem_cache_alloc(xfrm6_tunnel_spi_kmem, GFP_ATOMIC);
a922ba55	148	if (!x6spi)
1da177e4	149	goto out;
a922ba55	150
1da177e4 LT	151	memcpy(&x6spi->addr, saddr, sizeof(x6spi->addr));
1da177e4 LT	152	x6spi->spi = spi;
d12f3827	153	refcount_set(&x6spi->refcnt, 1);
1da177e4	154
a1664773	155	hlist_add_head_rcu(&x6spi->list_byspi, &xfrm6_tn->spi_byspi[index]);
1da177e4 LT	156
1da177e4 LT	157	index = xfrm6_tunnel_spi_hash_byaddr(saddr);
a1664773	158	hlist_add_head_rcu(&x6spi->list_byaddr, &xfrm6_tn->spi_byaddr[index]);
1da177e4	159	out:
1da177e4 LT	160	return spi;
	161	}
	162
a1664773	163	__be32 xfrm6_tunnel_alloc_spi(struct net net, xfrm_address_t saddr)
1da177e4 LT	164	{
	165	struct xfrm6_tunnel_spi *x6spi;
	166	u32 spi;
	167
91cc3bb0	168	spin_lock_bh(&xfrm6_tunnel_spi_lock);
a1664773	169	x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
1da177e4	170	if (x6spi) {
d12f3827	171	refcount_inc(&x6spi->refcnt);
1da177e4 LT	172	spi = x6spi->spi;
1da177e4 LT	173	} else
a1664773	174	spi = __xfrm6_tunnel_alloc_spi(net, saddr);
91cc3bb0	175	spin_unlock_bh(&xfrm6_tunnel_spi_lock);
1da177e4	176
5b122545	177	return htonl(spi);
1da177e4	178	}
1da177e4 LT	179	EXPORT_SYMBOL(xfrm6_tunnel_alloc_spi);
1da177e4 LT	180
91cc3bb0 ED	181	static void x6spi_destroy_rcu(struct rcu_head *head)
	182	{
	183	kmem_cache_free(xfrm6_tunnel_spi_kmem,
	184	container_of(head, struct xfrm6_tunnel_spi, rcu_head));
	185	}
	186
6f747aca	187	static void xfrm6_tunnel_free_spi(struct net net, xfrm_address_t saddr)
1da177e4	188	{
a1664773	189	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
1da177e4	190	struct xfrm6_tunnel_spi *x6spi;
b67bfe0d	191	struct hlist_node *n;
1da177e4	192
91cc3bb0	193	spin_lock_bh(&xfrm6_tunnel_spi_lock);
1da177e4	194
b67bfe0d	195	hlist_for_each_entry_safe(x6spi, n,
a1664773	196	&xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
1da177e4 LT	197	list_byaddr)
1da177e4 LT	198	{
ff88b30c	199	if (xfrm6_addr_equal(&x6spi->addr, saddr)) {
d12f3827	200	if (refcount_dec_and_test(&x6spi->refcnt)) {
91cc3bb0 ED	201	hlist_del_rcu(&x6spi->list_byaddr);
	202	hlist_del_rcu(&x6spi->list_byspi);
	203	call_rcu(&x6spi->rcu_head, x6spi_destroy_rcu);
1da177e4 LT	204	break;
	205	}
	206	}
	207	}
91cc3bb0	208	spin_unlock_bh(&xfrm6_tunnel_spi_lock);
1da177e4 LT	209	}
1da177e4 LT	210
1da177e4 LT	211	static int xfrm6_tunnel_output(struct xfrm_state x, struct sk_buff skb)
1da177e4 LT	212	{
7b277b1a	213	skb_push(skb, -skb_network_offset(skb));
1da177e4 LT	214	return 0;
	215	}
	216
e695633e	217	static int xfrm6_tunnel_input(struct xfrm_state x, struct sk_buff skb)
1da177e4	218	{
04663d0b	219	return skb_network_header(skb)[IP6CB(skb)->nhoff];
1da177e4 LT	220	}
1da177e4 LT	221
d2acc347	222	static int xfrm6_tunnel_rcv(struct sk_buff *skb)
1da177e4	223	{
a1664773	224	struct net *net = dev_net(skb->dev);
b71d1d42	225	const struct ipv6hdr *iph = ipv6_hdr(skb);
a252cc23	226	__be32 spi;
1da177e4	227
b71d1d42	228	spi = xfrm6_tunnel_spi_lookup(net, (const xfrm_address_t *)&iph->saddr);
63c43787	229	return xfrm6_rcv_spi(skb, IPPROTO_IPV6, spi, NULL);
1da177e4 LT	230	}
1da177e4 LT	231
d2acc347	232	static int xfrm6_tunnel_err(struct sk_buff skb, struct inet6_skb_parm opt,
d5fdd6ba	233	u8 type, u8 code, int offset, __be32 info)
1da177e4	234	{
1da177e4 LT	235	/* xfrm6_tunnel native err handling */
1da177e4 LT	236	switch (type) {
1ab1457c	237	case ICMPV6_DEST_UNREACH:
1da177e4	238	switch (code) {
1ab1457c	239	case ICMPV6_NOROUTE:
1da177e4 LT	240	case ICMPV6_ADM_PROHIBITED:
	241	case ICMPV6_NOT_NEIGHBOUR:
	242	case ICMPV6_ADDR_UNREACH:
	243	case ICMPV6_PORT_UNREACH:
	244	default:
1da177e4 LT	245	break;
	246	}
	247	break;
	248	case ICMPV6_PKT_TOOBIG:
1da177e4 LT	249	break;
	250	case ICMPV6_TIME_EXCEED:
	251	switch (code) {
	252	case ICMPV6_EXC_HOPLIMIT:
1da177e4 LT	253	break;
1da177e4 LT	254	case ICMPV6_EXC_FRAGTIME:
1ab1457c	255	default:
1da177e4 LT	256	break;
	257	}
	258	break;
	259	case ICMPV6_PARAMPROB:
	260	switch (code) {
	261	case ICMPV6_HDR_FIELD: break;
	262	case ICMPV6_UNK_NEXTHDR: break;
	263	case ICMPV6_UNK_OPTION: break;
	264	}
	265	break;
	266	default:
	267	break;
	268	}
d2acc347 HX	269
d2acc347 HX	270	return 0;
1da177e4 LT	271	}
1da177e4 LT	272
e1e10b44	273	static int xfrm6_tunnel_init_state(struct xfrm_state x, struct netlink_ext_ack extack)
1da177e4	274	{
25ec92cd SD	275	if (x->props.mode != XFRM_MODE_TUNNEL) {
25ec92cd SD	276	NL_SET_ERR_MSG(extack, "IPv6 tunnel can only be used with tunnel mode");
1da177e4	277	return -EINVAL;
25ec92cd	278	}
1da177e4	279
25ec92cd SD	280	if (x->encap) {
25ec92cd SD	281	NL_SET_ERR_MSG(extack, "IPv6 tunnel is not compatible with encapsulation");
1da177e4	282	return -EINVAL;
25ec92cd	283	}
1da177e4 LT	284
	285	x->props.header_len = sizeof(struct ipv6hdr);
	286
	287	return 0;
	288	}
	289
	290	static void xfrm6_tunnel_destroy(struct xfrm_state *x)
	291	{
a1664773 AD	292	struct net *net = xs_net(x);
	293
	294	xfrm6_tunnel_free_spi(net, (xfrm_address_t *)&x->props.saddr);
1da177e4 LT	295	}
1da177e4 LT	296
533cb5b0	297	static const struct xfrm_type xfrm6_tunnel_type = {
1da177e4 LT	298	.owner = THIS_MODULE,
	299	.proto = IPPROTO_IPV6,
	300	.init_state = xfrm6_tunnel_init_state,
	301	.destructor = xfrm6_tunnel_destroy,
	302	.input = xfrm6_tunnel_input,
	303	.output = xfrm6_tunnel_output,
	304	};
	305
3ff2cfa5	306	static struct xfrm6_tunnel xfrm6_tunnel_handler __read_mostly = {
1da177e4	307	.handler = xfrm6_tunnel_rcv,
d2acc347	308	.err_handler = xfrm6_tunnel_err,
7fe94612	309	.priority = 3,
1da177e4 LT	310	};
1da177e4 LT	311
3ff2cfa5	312	static struct xfrm6_tunnel xfrm46_tunnel_handler __read_mostly = {
73d605d1 KM	313	.handler = xfrm6_tunnel_rcv,
73d605d1 KM	314	.err_handler = xfrm6_tunnel_err,
7fe94612	315	.priority = 3,
73d605d1 KM	316	};
73d605d1 KM	317
a1664773 AD	318	static int __net_init xfrm6_tunnel_net_init(struct net *net)
	319	{
	320	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
	321	unsigned int i;
	322
	323	for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++)
	324	INIT_HLIST_HEAD(&xfrm6_tn->spi_byaddr[i]);
	325	for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++)
	326	INIT_HLIST_HEAD(&xfrm6_tn->spi_byspi[i]);
	327	xfrm6_tn->spi = 0;
	328
	329	return 0;
	330	}
	331
	332	static void __net_exit xfrm6_tunnel_net_exit(struct net *net)
	333	{
baeb0dbb VA	334	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
	335	unsigned int i;
	336
b48c05ab	337	xfrm_flush_gc();
dbb2483b	338	xfrm_state_flush(net, 0, false, true);
b48c05ab	339
baeb0dbb VA	340	for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++)
	341	WARN_ON_ONCE(!hlist_empty(&xfrm6_tn->spi_byaddr[i]));
	342
	343	for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++)
	344	WARN_ON_ONCE(!hlist_empty(&xfrm6_tn->spi_byspi[i]));
a1664773 AD	345	}
	346
	347	static struct pernet_operations xfrm6_tunnel_net_ops = {
	348	.init = xfrm6_tunnel_net_init,
	349	.exit = xfrm6_tunnel_net_exit,
	350	.id = &xfrm6_tunnel_net_id,
	351	.size = sizeof(struct xfrm6_tunnel_net),
	352	};
	353
1da177e4 LT	354	static int __init xfrm6_tunnel_init(void)
1da177e4 LT	355	{
e924960d AD	356	int rv;
e924960d AD	357
d5aa407f AD	358	xfrm6_tunnel_spi_kmem = kmem_cache_create("xfrm6_tunnel_spi",
	359	sizeof(struct xfrm6_tunnel_spi),
	360	0, SLAB_HWCACHE_ALIGN,
	361	NULL);
	362	if (!xfrm6_tunnel_spi_kmem)
	363	return -ENOMEM;
	364	rv = register_pernet_subsys(&xfrm6_tunnel_net_ops);
	365	if (rv < 0)
	366	goto out_pernet;
e924960d AD	367	rv = xfrm_register_type(&xfrm6_tunnel_type, AF_INET6);
e924960d AD	368	if (rv < 0)
d5aa407f	369	goto out_type;
e924960d AD	370	rv = xfrm6_tunnel_register(&xfrm6_tunnel_handler, AF_INET6);
e924960d AD	371	if (rv < 0)
d5aa407f	372	goto out_xfrm6;
e924960d AD	373	rv = xfrm6_tunnel_register(&xfrm46_tunnel_handler, AF_INET);
e924960d AD	374	if (rv < 0)
d5aa407f	375	goto out_xfrm46;
1da177e4	376	return 0;
5ce1bbb9	377
d5aa407f	378	out_xfrm46:
5ce1bbb9	379	xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
d5aa407f	380	out_xfrm6:
5ce1bbb9	381	xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
d5aa407f AD	382	out_type:
	383	unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
	384	out_pernet:
	385	kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
e924960d	386	return rv;
1da177e4 LT	387	}
	388
	389	static void __exit xfrm6_tunnel_fini(void)
	390	{
73d605d1 KM	391	xfrm6_tunnel_deregister(&xfrm46_tunnel_handler, AF_INET);
73d605d1 KM	392	xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
a922ba55	393	xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
d5aa407f	394	unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
6ee02a54 SY	395	/* Someone maybe has gotten the xfrm6_tunnel_spi.
	396	* So need to wait it.
	397	*/
	398	rcu_barrier();
d5aa407f	399	kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
1da177e4 LT	400	}
	401
	402	module_init(xfrm6_tunnel_init);
	403	module_exit(xfrm6_tunnel_fini);
	404	MODULE_LICENSE("GPL");
d3d6dd3a	405	MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_IPV6);