[net-next-2.6.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, 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>
 *
 * Based on net/ipv4/xfrm4_tunnel.c
 *
 */
#include <linux/module.h>
#include <linux/xfrm.h>
#include <linux/list.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>

#ifdef CONFIG_IPV6_XFRM6_TUNNEL_DEBUG
# define X6TDEBUG	3
#else
# define X6TDEBUG	1
#endif

#define X6TPRINTK(fmt, args...)		printk(fmt, ## args)
#define X6TNOPRINTK(fmt, args...)	do { ; } while(0)

#if X6TDEBUG >= 1
# define X6TPRINTK1	X6TPRINTK
#else
# define X6TPRINTK1	X6TNOPRINTK
#endif

#if X6TDEBUG >= 3
# define X6TPRINTK3	X6TPRINTK
#else
# define X6TPRINTK3	X6TNOPRINTK
#endif

/*
 * 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;
#ifdef XFRM6_TUNNEL_SPI_MAGIC
	u32 magic;
#endif
};

#ifdef CONFIG_IPV6_XFRM6_TUNNEL_DEBUG
# define XFRM6_TUNNEL_SPI_MAGIC 0xdeadbeef
#endif

static DEFINE_RWLOCK(xfrm6_tunnel_spi_lock);

static u32 xfrm6_tunnel_spi;

#define XFRM6_TUNNEL_SPI_MIN	1
#define XFRM6_TUNNEL_SPI_MAX	0xffffffff

static kmem_cache_t *xfrm6_tunnel_spi_kmem __read_mostly;

#define XFRM6_TUNNEL_SPI_BYADDR_HSIZE 256
#define XFRM6_TUNNEL_SPI_BYSPI_HSIZE 256

static struct hlist_head xfrm6_tunnel_spi_byaddr[XFRM6_TUNNEL_SPI_BYADDR_HSIZE];
static struct hlist_head xfrm6_tunnel_spi_byspi[XFRM6_TUNNEL_SPI_BYSPI_HSIZE];

#ifdef XFRM6_TUNNEL_SPI_MAGIC
static int x6spi_check_magic(const struct xfrm6_tunnel_spi *x6spi,
			     const char *name)
{
	if (unlikely(x6spi->magic != XFRM6_TUNNEL_SPI_MAGIC)) {
		X6TPRINTK3(KERN_DEBUG "%s(): x6spi object "
				      "at %p has corrupted magic %08x "
				      "(should be %08x)\n",
			   name, x6spi, x6spi->magic, XFRM6_TUNNEL_SPI_MAGIC);
		return -1;
	}
	return 0;
}
#else
static int inline x6spi_check_magic(const struct xfrm6_tunnel_spi *x6spi,
				    const char *name)
{
	return 0;
}
#endif

#define X6SPI_CHECK_MAGIC(x6spi) x6spi_check_magic((x6spi), __FUNCTION__)


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

	X6TPRINTK3(KERN_DEBUG "%s(addr=%p)\n", __FUNCTION__, addr);

	h = addr->a6[0] ^ addr->a6[1] ^ addr->a6[2] ^ addr->a6[3];
	h ^= h >> 16;
	h ^= h >> 8;
	h &= XFRM6_TUNNEL_SPI_BYADDR_HSIZE - 1;

	X6TPRINTK3(KERN_DEBUG "%s() = %u\n", __FUNCTION__, h);

	return h;
}

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


static int xfrm6_tunnel_spi_init(void)
{
	int i;

	X6TPRINTK3(KERN_DEBUG "%s()\n", __FUNCTION__);

	xfrm6_tunnel_spi = 0;
	xfrm6_tunnel_spi_kmem = kmem_cache_create("xfrm6_tunnel_spi",
						  sizeof(struct xfrm6_tunnel_spi),
						  0, SLAB_HWCACHE_ALIGN,
						  NULL, NULL);
	if (!xfrm6_tunnel_spi_kmem) {
		X6TPRINTK1(KERN_ERR
			   "%s(): failed to allocate xfrm6_tunnel_spi_kmem\n",
		           __FUNCTION__);
		return -ENOMEM;
	}

	for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++)
		INIT_HLIST_HEAD(&xfrm6_tunnel_spi_byaddr[i]);
	for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++)
		INIT_HLIST_HEAD(&xfrm6_tunnel_spi_byspi[i]);
	return 0;
}

static void xfrm6_tunnel_spi_fini(void)
{
	int i;

	X6TPRINTK3(KERN_DEBUG "%s()\n", __FUNCTION__);

	for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++) {
		if (!hlist_empty(&xfrm6_tunnel_spi_byaddr[i]))
			goto err;
	}
	for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++) {
		if (!hlist_empty(&xfrm6_tunnel_spi_byspi[i]))
			goto err;
	}
	kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
	xfrm6_tunnel_spi_kmem = NULL;
	return;
err:
	X6TPRINTK1(KERN_ERR "%s(): table is not empty\n", __FUNCTION__);
	return;
}

static struct xfrm6_tunnel_spi *__xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr)
{
	struct xfrm6_tunnel_spi *x6spi;
	struct hlist_node *pos;

	X6TPRINTK3(KERN_DEBUG "%s(saddr=%p)\n", __FUNCTION__, saddr);

	hlist_for_each_entry(x6spi, pos,
			     &xfrm6_tunnel_spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
			     list_byaddr) {
		if (memcmp(&x6spi->addr, saddr, sizeof(x6spi->addr)) == 0) {
			X6SPI_CHECK_MAGIC(x6spi);
			X6TPRINTK3(KERN_DEBUG "%s() = %p(%u)\n", __FUNCTION__, x6spi, x6spi->spi);
			return x6spi;
		}
	}

	X6TPRINTK3(KERN_DEBUG "%s() = NULL(0)\n", __FUNCTION__);
	return NULL;
}

u32 xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr)
{
	struct xfrm6_tunnel_spi *x6spi;
	u32 spi;

	X6TPRINTK3(KERN_DEBUG "%s(saddr=%p)\n", __FUNCTION__, saddr);

	read_lock_bh(&xfrm6_tunnel_spi_lock);
	x6spi = __xfrm6_tunnel_spi_lookup(saddr);
	spi = x6spi ? x6spi->spi : 0;
	read_unlock_bh(&xfrm6_tunnel_spi_lock);
	return spi;
}

EXPORT_SYMBOL(xfrm6_tunnel_spi_lookup);

static u32 __xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr)
{
	u32 spi;
	struct xfrm6_tunnel_spi *x6spi;
	struct hlist_node *pos;
	unsigned index;

	X6TPRINTK3(KERN_DEBUG "%s(saddr=%p)\n", __FUNCTION__, saddr);

	if (xfrm6_tunnel_spi < XFRM6_TUNNEL_SPI_MIN ||
	    xfrm6_tunnel_spi >= XFRM6_TUNNEL_SPI_MAX)
		xfrm6_tunnel_spi = XFRM6_TUNNEL_SPI_MIN;
	else
		xfrm6_tunnel_spi++;

	for (spi = xfrm6_tunnel_spi; spi <= XFRM6_TUNNEL_SPI_MAX; spi++) {
		index = xfrm6_tunnel_spi_hash_byspi(spi);
		hlist_for_each_entry(x6spi, pos, 
				     &xfrm6_tunnel_spi_byspi[index], 
				     list_byspi) {
			if (x6spi->spi == spi)
				goto try_next_1;
		}
		xfrm6_tunnel_spi = spi;
		goto alloc_spi;
try_next_1:;
	}
	for (spi = XFRM6_TUNNEL_SPI_MIN; spi < xfrm6_tunnel_spi; spi++) {
		index = xfrm6_tunnel_spi_hash_byspi(spi);
		hlist_for_each_entry(x6spi, pos, 
				     &xfrm6_tunnel_spi_byspi[index], 
				     list_byspi) {
			if (x6spi->spi == spi)
				goto try_next_2;
		}
		xfrm6_tunnel_spi = spi;
		goto alloc_spi;
try_next_2:;
	}
	spi = 0;
	goto out;
alloc_spi:
	X6TPRINTK3(KERN_DEBUG "%s(): allocate new spi for " NIP6_FMT "\n",
			      __FUNCTION__, 
			      NIP6(*(struct in6_addr *)saddr));
	x6spi = kmem_cache_alloc(xfrm6_tunnel_spi_kmem, SLAB_ATOMIC);
	if (!x6spi) {
		X6TPRINTK1(KERN_ERR "%s(): kmem_cache_alloc() failed\n", 
			   __FUNCTION__);
		goto out;
	}
#ifdef XFRM6_TUNNEL_SPI_MAGIC
	x6spi->magic = XFRM6_TUNNEL_SPI_MAGIC;
#endif
	memcpy(&x6spi->addr, saddr, sizeof(x6spi->addr));
	x6spi->spi = spi;
	atomic_set(&x6spi->refcnt, 1);

	hlist_add_head(&x6spi->list_byspi, &xfrm6_tunnel_spi_byspi[index]);

	index = xfrm6_tunnel_spi_hash_byaddr(saddr);
	hlist_add_head(&x6spi->list_byaddr, &xfrm6_tunnel_spi_byaddr[index]);
	X6SPI_CHECK_MAGIC(x6spi);
out:
	X6TPRINTK3(KERN_DEBUG "%s() = %u\n", __FUNCTION__, spi);
	return spi;
}

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

	X6TPRINTK3(KERN_DEBUG "%s(saddr=%p)\n", __FUNCTION__, saddr);

	write_lock_bh(&xfrm6_tunnel_spi_lock);
	x6spi = __xfrm6_tunnel_spi_lookup(saddr);
	if (x6spi) {
		atomic_inc(&x6spi->refcnt);
		spi = x6spi->spi;
	} else
		spi = __xfrm6_tunnel_alloc_spi(saddr);
	write_unlock_bh(&xfrm6_tunnel_spi_lock);

	X6TPRINTK3(KERN_DEBUG "%s() = %u\n", __FUNCTION__, spi);

	return spi;
}

EXPORT_SYMBOL(xfrm6_tunnel_alloc_spi);

void xfrm6_tunnel_free_spi(xfrm_address_t *saddr)
{
	struct xfrm6_tunnel_spi *x6spi;
	struct hlist_node *pos, *n;

	X6TPRINTK3(KERN_DEBUG "%s(saddr=%p)\n", __FUNCTION__, saddr);

	write_lock_bh(&xfrm6_tunnel_spi_lock);

	hlist_for_each_entry_safe(x6spi, pos, n, 
				  &xfrm6_tunnel_spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
				  list_byaddr)
	{
		if (memcmp(&x6spi->addr, saddr, sizeof(x6spi->addr)) == 0) {
			X6TPRINTK3(KERN_DEBUG "%s(): x6spi object for " NIP6_FMT 
					      " found at %p\n",
				   __FUNCTION__, 
				   NIP6(*(struct in6_addr *)saddr),
				   x6spi);
			X6SPI_CHECK_MAGIC(x6spi);
			if (atomic_dec_and_test(&x6spi->refcnt)) {
				hlist_del(&x6spi->list_byaddr);
				hlist_del(&x6spi->list_byspi);
				kmem_cache_free(xfrm6_tunnel_spi_kmem, x6spi);
				break;
			}
		}
	}
	write_unlock_bh(&xfrm6_tunnel_spi_lock);
}

EXPORT_SYMBOL(xfrm6_tunnel_free_spi);

static int xfrm6_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
{
	struct ipv6hdr *top_iph;

	top_iph = (struct ipv6hdr *)skb->data;
	top_iph->payload_len = htons(skb->len - sizeof(struct ipv6hdr));

	return 0;
}

static int xfrm6_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
{
	return 0;
}

static int xfrm6_tunnel_rcv(struct sk_buff *skb)
{
	struct ipv6hdr *iph = skb->nh.ipv6h;
	u32 spi;

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

static int xfrm6_tunnel_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
			    int type, int code, int offset, __u32 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:
			X6TPRINTK3(KERN_DEBUG
				   "xfrm6_tunnel: Destination Unreach.\n");
			break;
		}
		break;
	case ICMPV6_PKT_TOOBIG:
			X6TPRINTK3(KERN_DEBUG 
				   "xfrm6_tunnel: Packet Too Big.\n");
		break;
	case ICMPV6_TIME_EXCEED:
		switch (code) {
		case ICMPV6_EXC_HOPLIMIT:
			X6TPRINTK3(KERN_DEBUG
				   "xfrm6_tunnel: Too small Hoplimit.\n");
			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)
		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)
{
	xfrm6_tunnel_free_spi((xfrm_address_t *)&x->props.saddr);
}

static 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 = {
	.handler	= xfrm6_tunnel_rcv,
	.err_handler	= xfrm6_tunnel_err,
	.priority	= 2,
};

static int __init xfrm6_tunnel_init(void)
{
	X6TPRINTK3(KERN_DEBUG "%s()\n", __FUNCTION__);

	if (xfrm_register_type(&xfrm6_tunnel_type, AF_INET6) < 0) {
		X6TPRINTK1(KERN_ERR
			   "xfrm6_tunnel init: can't add xfrm type\n");
		return -EAGAIN;
	}
	if (xfrm6_tunnel_register(&xfrm6_tunnel_handler)) {
		X6TPRINTK1(KERN_ERR
			   "xfrm6_tunnel init(): can't add handler\n");
		xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
		return -EAGAIN;
	}
	if (xfrm6_tunnel_spi_init() < 0) {
		X6TPRINTK1(KERN_ERR
			   "xfrm6_tunnel init: failed to initialize spi\n");
		xfrm6_tunnel_deregister(&xfrm6_tunnel_handler);
		xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
		return -EAGAIN;
	}
	return 0;
}

static void __exit xfrm6_tunnel_fini(void)
{
	X6TPRINTK3(KERN_DEBUG "%s()\n", __FUNCTION__);

	xfrm6_tunnel_spi_fini();
	if (xfrm6_tunnel_deregister(&xfrm6_tunnel_handler))
		X6TPRINTK1(KERN_ERR 
			   "xfrm6_tunnel close: can't remove handler\n");
	if (xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6) < 0)
		X6TPRINTK1(KERN_ERR
			   "xfrm6_tunnel close: can't remove xfrm type\n");
}

module_init(xfrm6_tunnel_init);
module_exit(xfrm6_tunnel_fini);
MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	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	* Based on net/ipv4/xfrm4_tunnel.c
	22	*
	23	*/
1da177e4 LT	24	#include <linux/module.h>
	25	#include <linux/xfrm.h>
	26	#include <linux/list.h>
	27	#include <net/ip.h>
	28	#include <net/xfrm.h>
	29	#include <net/ipv6.h>
1da177e4 LT	30	#include <linux/ipv6.h>
1da177e4 LT	31	#include <linux/icmpv6.h>
4a3e2f71	32	#include <linux/mutex.h>
1da177e4 LT	33
	34	#ifdef CONFIG_IPV6_XFRM6_TUNNEL_DEBUG
	35	# define X6TDEBUG 3
	36	#else
	37	# define X6TDEBUG 1
	38	#endif
	39
	40	#define X6TPRINTK(fmt, args...) printk(fmt, ## args)
	41	#define X6TNOPRINTK(fmt, args...) do { ; } while(0)
	42
	43	#if X6TDEBUG >= 1
	44	# define X6TPRINTK1 X6TPRINTK
	45	#else
	46	# define X6TPRINTK1 X6TNOPRINTK
	47	#endif
	48
	49	#if X6TDEBUG >= 3
	50	# define X6TPRINTK3 X6TPRINTK
	51	#else
	52	# define X6TPRINTK3 X6TNOPRINTK
	53	#endif
	54
	55	/*
	56	* xfrm_tunnel_spi things are for allocating unique id ("spi")
	57	* per xfrm_address_t.
	58	*/
	59	struct xfrm6_tunnel_spi {
	60	struct hlist_node list_byaddr;
	61	struct hlist_node list_byspi;
	62	xfrm_address_t addr;
	63	u32 spi;
	64	atomic_t refcnt;
	65	#ifdef XFRM6_TUNNEL_SPI_MAGIC
	66	u32 magic;
	67	#endif
	68	};
	69
	70	#ifdef CONFIG_IPV6_XFRM6_TUNNEL_DEBUG
	71	# define XFRM6_TUNNEL_SPI_MAGIC 0xdeadbeef
	72	#endif
	73
	74	static DEFINE_RWLOCK(xfrm6_tunnel_spi_lock);
	75
	76	static u32 xfrm6_tunnel_spi;
	77
	78	#define XFRM6_TUNNEL_SPI_MIN 1
	79	#define XFRM6_TUNNEL_SPI_MAX 0xffffffff
	80
ba89966c	81	static kmem_cache_t *xfrm6_tunnel_spi_kmem __read_mostly;
1da177e4 LT	82
	83	#define XFRM6_TUNNEL_SPI_BYADDR_HSIZE 256
	84	#define XFRM6_TUNNEL_SPI_BYSPI_HSIZE 256
	85
	86	static struct hlist_head xfrm6_tunnel_spi_byaddr[XFRM6_TUNNEL_SPI_BYADDR_HSIZE];
	87	static struct hlist_head xfrm6_tunnel_spi_byspi[XFRM6_TUNNEL_SPI_BYSPI_HSIZE];
	88
	89	#ifdef XFRM6_TUNNEL_SPI_MAGIC
	90	static int x6spi_check_magic(const struct xfrm6_tunnel_spi *x6spi,
	91	const char *name)
	92	{
	93	if (unlikely(x6spi->magic != XFRM6_TUNNEL_SPI_MAGIC)) {
	94	X6TPRINTK3(KERN_DEBUG "%s(): x6spi object "
	95	"at %p has corrupted magic %08x "
	96	"(should be %08x)\n",
	97	name, x6spi, x6spi->magic, XFRM6_TUNNEL_SPI_MAGIC);
	98	return -1;
	99	}
	100	return 0;
	101	}
	102	#else
	103	static int inline x6spi_check_magic(const struct xfrm6_tunnel_spi *x6spi,
	104	const char *name)
	105	{
	106	return 0;
	107	}
	108	#endif
	109
	110	#define X6SPI_CHECK_MAGIC(x6spi) x6spi_check_magic((x6spi), __FUNCTION__)
	111
	112
	113	static unsigned inline xfrm6_tunnel_spi_hash_byaddr(xfrm_address_t *addr)
	114	{
	115	unsigned h;
	116
	117	X6TPRINTK3(KERN_DEBUG "%s(addr=%p)\n", __FUNCTION__, addr);
	118
	119	h = addr->a6[0] ^ addr->a6[1] ^ addr->a6[2] ^ addr->a6[3];
	120	h ^= h >> 16;
	121	h ^= h >> 8;
	122	h &= XFRM6_TUNNEL_SPI_BYADDR_HSIZE - 1;
	123
	124	X6TPRINTK3(KERN_DEBUG "%s() = %u\n", __FUNCTION__, h);
	125
	126	return h;
	127	}
	128
	129	static unsigned inline xfrm6_tunnel_spi_hash_byspi(u32 spi)
	130	{
	131	return spi % XFRM6_TUNNEL_SPI_BYSPI_HSIZE;
	132	}
	133
	134
	135	static int xfrm6_tunnel_spi_init(void)
	136	{
	137	int i;
	138
	139	X6TPRINTK3(KERN_DEBUG "%s()\n", __FUNCTION__);
	140
	141	xfrm6_tunnel_spi = 0;
	142	xfrm6_tunnel_spi_kmem = kmem_cache_create("xfrm6_tunnel_spi",
	143	sizeof(struct xfrm6_tunnel_spi),
	144	0, SLAB_HWCACHE_ALIGN,
	145	NULL, NULL);
146	if (!xfrm6_tunnel_spi_kmem) {
147	X6TPRINTK1(KERN_ERR
148	"%s(): failed to allocate xfrm6_tunnel_spi_kmem\n",
149	__FUNCTION__);
150	return -ENOMEM;
151	}
152
153	for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++)
154	INIT_HLIST_HEAD(&xfrm6_tunnel_spi_byaddr[i]);
155	for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++)
156	INIT_HLIST_HEAD(&xfrm6_tunnel_spi_byspi[i]);
157	return 0;
158	}
159
160	static void xfrm6_tunnel_spi_fini(void)
161	{
162	int i;
163
164	X6TPRINTK3(KERN_DEBUG "%s()\n", __FUNCTION__);
165
166	for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++) {
167	if (!hlist_empty(&xfrm6_tunnel_spi_byaddr[i]))
168	goto err;
169	}
170	for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++) {
171	if (!hlist_empty(&xfrm6_tunnel_spi_byspi[i]))
172	goto err;
173	}
174	kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
175	xfrm6_tunnel_spi_kmem = NULL;
176	return;
177	err:
178	X6TPRINTK1(KERN_ERR "%s(): table is not empty\n", __FUNCTION__);
179	return;
180	}
181
182	static struct xfrm6_tunnel_spi __xfrm6_tunnel_spi_lookup(xfrm_address_t saddr)
183	{
184	struct xfrm6_tunnel_spi *x6spi;
185	struct hlist_node *pos;
186
187	X6TPRINTK3(KERN_DEBUG "%s(saddr=%p)\n", __FUNCTION__, saddr);
188
189	hlist_for_each_entry(x6spi, pos,
190	&xfrm6_tunnel_spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
191	list_byaddr) {
192	if (memcmp(&x6spi->addr, saddr, sizeof(x6spi->addr)) == 0) {
193	X6SPI_CHECK_MAGIC(x6spi);
194	X6TPRINTK3(KERN_DEBUG "%s() = %p(%u)\n", __FUNCTION__, x6spi, x6spi->spi);
195	return x6spi;
196	}
197	}
198
199	X6TPRINTK3(KERN_DEBUG "%s() = NULL(0)\n", __FUNCTION__);
200	return NULL;
201	}
202
203	u32 xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr)
204	{
205	struct xfrm6_tunnel_spi *x6spi;
206	u32 spi;
207
208	X6TPRINTK3(KERN_DEBUG "%s(saddr=%p)\n", __FUNCTION__, saddr);
209
210	read_lock_bh(&xfrm6_tunnel_spi_lock);
211	x6spi = __xfrm6_tunnel_spi_lookup(saddr);
212	spi = x6spi ? x6spi->spi : 0;
213	read_unlock_bh(&xfrm6_tunnel_spi_lock);
214	return spi;
215	}
216
217	EXPORT_SYMBOL(xfrm6_tunnel_spi_lookup);
218
219	static u32 __xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr)
220	{
221	u32 spi;
222	struct xfrm6_tunnel_spi *x6spi;
223	struct hlist_node *pos;
224	unsigned index;
225
226	X6TPRINTK3(KERN_DEBUG "%s(saddr=%p)\n", __FUNCTION__, saddr);
227
228	if (xfrm6_tunnel_spi < XFRM6_TUNNEL_SPI_MIN \|\|
229	xfrm6_tunnel_spi >= XFRM6_TUNNEL_SPI_MAX)
230	xfrm6_tunnel_spi = XFRM6_TUNNEL_SPI_MIN;
231	else
232	xfrm6_tunnel_spi++;
233
234	for (spi = xfrm6_tunnel_spi; spi <= XFRM6_TUNNEL_SPI_MAX; spi++) {
235	index = xfrm6_tunnel_spi_hash_byspi(spi);
236	hlist_for_each_entry(x6spi, pos,
237	&xfrm6_tunnel_spi_byspi[index],
238	list_byspi) {
239	if (x6spi->spi == spi)
240	goto try_next_1;
241	}
242	xfrm6_tunnel_spi = spi;
243	goto alloc_spi;
244	try_next_1:;
245	}
246	for (spi = XFRM6_TUNNEL_SPI_MIN; spi < xfrm6_tunnel_spi; spi++) {
247	index = xfrm6_tunnel_spi_hash_byspi(spi);
248	hlist_for_each_entry(x6spi, pos,
249	&xfrm6_tunnel_spi_byspi[index],
250	list_byspi) {
251	if (x6spi->spi == spi)
252	goto try_next_2;
253	}
254	xfrm6_tunnel_spi = spi;
255	goto alloc_spi;
256	try_next_2:;
257	}
258	spi = 0;
259	goto out;
260	alloc_spi:
46b86a2d	261	X6TPRINTK3(KERN_DEBUG "%s(): allocate new spi for " NIP6_FMT "\n",
1da177e4 LT	262	__FUNCTION__,
	263	NIP6((struct in6_addr )saddr));
	264	x6spi = kmem_cache_alloc(xfrm6_tunnel_spi_kmem, SLAB_ATOMIC);
	265	if (!x6spi) {
	266	X6TPRINTK1(KERN_ERR "%s(): kmem_cache_alloc() failed\n",
	267	__FUNCTION__);
	268	goto out;
	269	}
	270	#ifdef XFRM6_TUNNEL_SPI_MAGIC
	271	x6spi->magic = XFRM6_TUNNEL_SPI_MAGIC;
	272	#endif
	273	memcpy(&x6spi->addr, saddr, sizeof(x6spi->addr));
	274	x6spi->spi = spi;
	275	atomic_set(&x6spi->refcnt, 1);
	276
	277	hlist_add_head(&x6spi->list_byspi, &xfrm6_tunnel_spi_byspi[index]);
	278
	279	index = xfrm6_tunnel_spi_hash_byaddr(saddr);
	280	hlist_add_head(&x6spi->list_byaddr, &xfrm6_tunnel_spi_byaddr[index]);
	281	X6SPI_CHECK_MAGIC(x6spi);
	282	out:
	283	X6TPRINTK3(KERN_DEBUG "%s() = %u\n", __FUNCTION__, spi);
	284	return spi;
	285	}
	286
	287	u32 xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr)
	288	{
	289	struct xfrm6_tunnel_spi *x6spi;
	290	u32 spi;
	291
	292	X6TPRINTK3(KERN_DEBUG "%s(saddr=%p)\n", __FUNCTION__, saddr);
	293
	294	write_lock_bh(&xfrm6_tunnel_spi_lock);
	295	x6spi = __xfrm6_tunnel_spi_lookup(saddr);
	296	if (x6spi) {
	297	atomic_inc(&x6spi->refcnt);
	298	spi = x6spi->spi;
	299	} else
	300	spi = __xfrm6_tunnel_alloc_spi(saddr);
	301	write_unlock_bh(&xfrm6_tunnel_spi_lock);
	302
	303	X6TPRINTK3(KERN_DEBUG "%s() = %u\n", __FUNCTION__, spi);
	304
	305	return spi;
	306	}
	307
	308	EXPORT_SYMBOL(xfrm6_tunnel_alloc_spi);
	309
	310	void xfrm6_tunnel_free_spi(xfrm_address_t *saddr)
	311	{
	312	struct xfrm6_tunnel_spi *x6spi;
	313	struct hlist_node pos, n;
	314
	315	X6TPRINTK3(KERN_DEBUG "%s(saddr=%p)\n", __FUNCTION__, saddr);
	316
	317	write_lock_bh(&xfrm6_tunnel_spi_lock);
	318
	319	hlist_for_each_entry_safe(x6spi, pos, n,
	320	&xfrm6_tunnel_spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
	321	list_byaddr)
	322	{
	323	if (memcmp(&x6spi->addr, saddr, sizeof(x6spi->addr)) == 0) {
46b86a2d JP	324	X6TPRINTK3(KERN_DEBUG "%s(): x6spi object for " NIP6_FMT
46b86a2d JP	325	" found at %p\n",
1da177e4 LT	326	__FUNCTION__,
	327	NIP6((struct in6_addr )saddr),
	328	x6spi);
	329	X6SPI_CHECK_MAGIC(x6spi);
	330	if (atomic_dec_and_test(&x6spi->refcnt)) {
	331	hlist_del(&x6spi->list_byaddr);
	332	hlist_del(&x6spi->list_byspi);
	333	kmem_cache_free(xfrm6_tunnel_spi_kmem, x6spi);
	334	break;
	335	}
	336	}
	337	}
	338	write_unlock_bh(&xfrm6_tunnel_spi_lock);
	339	}
	340
	341	EXPORT_SYMBOL(xfrm6_tunnel_free_spi);
	342
	343	static int xfrm6_tunnel_output(struct xfrm_state x, struct sk_buff skb)
	344	{
	345	struct ipv6hdr *top_iph;
	346
	347	top_iph = (struct ipv6hdr *)skb->data;
	348	top_iph->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
	349
	350	return 0;
	351	}
	352
e695633e	353	static int xfrm6_tunnel_input(struct xfrm_state x, struct sk_buff skb)
1da177e4 LT	354	{
	355	return 0;
	356	}
	357
d2acc347	358	static int xfrm6_tunnel_rcv(struct sk_buff *skb)
1da177e4	359	{
1da177e4 LT	360	struct ipv6hdr *iph = skb->nh.ipv6h;
	361	u32 spi;
	362
1da177e4	363	spi = xfrm6_tunnel_spi_lookup((xfrm_address_t *)&iph->saddr);
d2acc347	364	return xfrm6_rcv_spi(skb, spi);
1da177e4 LT	365	}
1da177e4 LT	366
d2acc347 HX	367	static int xfrm6_tunnel_err(struct sk_buff skb, struct inet6_skb_parm opt,
d2acc347 HX	368	int type, int code, int offset, __u32 info)
1da177e4	369	{
1da177e4 LT	370	/* xfrm6_tunnel native err handling */
	371	switch (type) {
	372	case ICMPV6_DEST_UNREACH:
	373	switch (code) {
	374	case ICMPV6_NOROUTE:
	375	case ICMPV6_ADM_PROHIBITED:
	376	case ICMPV6_NOT_NEIGHBOUR:
	377	case ICMPV6_ADDR_UNREACH:
	378	case ICMPV6_PORT_UNREACH:
	379	default:
	380	X6TPRINTK3(KERN_DEBUG
	381	"xfrm6_tunnel: Destination Unreach.\n");
	382	break;
	383	}
	384	break;
	385	case ICMPV6_PKT_TOOBIG:
	386	X6TPRINTK3(KERN_DEBUG
	387	"xfrm6_tunnel: Packet Too Big.\n");
	388	break;
	389	case ICMPV6_TIME_EXCEED:
	390	switch (code) {
	391	case ICMPV6_EXC_HOPLIMIT:
	392	X6TPRINTK3(KERN_DEBUG
	393	"xfrm6_tunnel: Too small Hoplimit.\n");
	394	break;
	395	case ICMPV6_EXC_FRAGTIME:
	396	default:
	397	break;
	398	}
	399	break;
	400	case ICMPV6_PARAMPROB:
	401	switch (code) {
	402	case ICMPV6_HDR_FIELD: break;
	403	case ICMPV6_UNK_NEXTHDR: break;
	404	case ICMPV6_UNK_OPTION: break;
	405	}
	406	break;
	407	default:
	408	break;
	409	}
d2acc347 HX	410
d2acc347 HX	411	return 0;
1da177e4 LT	412	}
1da177e4 LT	413
72cb6962	414	static int xfrm6_tunnel_init_state(struct xfrm_state *x)
1da177e4 LT	415	{
	416	if (!x->props.mode)
	417	return -EINVAL;
	418
	419	if (x->encap)
	420	return -EINVAL;
	421
	422	x->props.header_len = sizeof(struct ipv6hdr);
	423
	424	return 0;
	425	}
	426
	427	static void xfrm6_tunnel_destroy(struct xfrm_state *x)
	428	{
	429	xfrm6_tunnel_free_spi((xfrm_address_t *)&x->props.saddr);
	430	}
	431
	432	static struct xfrm_type xfrm6_tunnel_type = {
	433	.description = "IP6IP6",
	434	.owner = THIS_MODULE,
	435	.proto = IPPROTO_IPV6,
	436	.init_state = xfrm6_tunnel_init_state,
	437	.destructor = xfrm6_tunnel_destroy,
	438	.input = xfrm6_tunnel_input,
	439	.output = xfrm6_tunnel_output,
	440	};
	441
d2acc347	442	static struct xfrm6_tunnel xfrm6_tunnel_handler = {
1da177e4	443	.handler = xfrm6_tunnel_rcv,
d2acc347 HX	444	.err_handler = xfrm6_tunnel_err,
d2acc347 HX	445	.priority = 2,
1da177e4 LT	446	};
	447
	448	static int __init xfrm6_tunnel_init(void)
	449	{
	450	X6TPRINTK3(KERN_DEBUG "%s()\n", __FUNCTION__);
	451
	452	if (xfrm_register_type(&xfrm6_tunnel_type, AF_INET6) < 0) {
	453	X6TPRINTK1(KERN_ERR
	454	"xfrm6_tunnel init: can't add xfrm type\n");
	455	return -EAGAIN;
	456	}
d2acc347	457	if (xfrm6_tunnel_register(&xfrm6_tunnel_handler)) {
1da177e4	458	X6TPRINTK1(KERN_ERR
d2acc347	459	"xfrm6_tunnel init(): can't add handler\n");
1da177e4 LT	460	xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
	461	return -EAGAIN;
	462	}
	463	if (xfrm6_tunnel_spi_init() < 0) {
	464	X6TPRINTK1(KERN_ERR
	465	"xfrm6_tunnel init: failed to initialize spi\n");
d2acc347	466	xfrm6_tunnel_deregister(&xfrm6_tunnel_handler);
1da177e4 LT	467	xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
	468	return -EAGAIN;
	469	}
	470	return 0;
	471	}
	472
	473	static void __exit xfrm6_tunnel_fini(void)
	474	{
	475	X6TPRINTK3(KERN_DEBUG "%s()\n", __FUNCTION__);
	476
	477	xfrm6_tunnel_spi_fini();
d2acc347	478	if (xfrm6_tunnel_deregister(&xfrm6_tunnel_handler))
1da177e4	479	X6TPRINTK1(KERN_ERR
d2acc347	480	"xfrm6_tunnel close: can't remove handler\n");
1da177e4 LT	481	if (xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6) < 0)
	482	X6TPRINTK1(KERN_ERR
	483	"xfrm6_tunnel close: can't remove xfrm type\n");
	484	}
	485
	486	module_init(xfrm6_tunnel_init);
	487	module_exit(xfrm6_tunnel_fini);
	488	MODULE_LICENSE("GPL");