/*
* 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/config.h>
#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 <net/protocol.h>
#include <linux/ipv6.h>
#include <linux/icmpv6.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 xfrm_decap_state *decap, struct sk_buff *skb)
{
return 0;
}
static struct xfrm6_tunnel *xfrm6_tunnel_handler;
static DECLARE_MUTEX(xfrm6_tunnel_sem);
int xfrm6_tunnel_register(struct xfrm6_tunnel *handler)
{
int ret;
down(&xfrm6_tunnel_sem);
ret = 0;
if (xfrm6_tunnel_handler != NULL)
ret = -EINVAL;
if (!ret)
xfrm6_tunnel_handler = handler;
up(&xfrm6_tunnel_sem);
return ret;
}
EXPORT_SYMBOL(xfrm6_tunnel_register);
int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler)
{
int ret;
down(&xfrm6_tunnel_sem);
ret = 0;
if (xfrm6_tunnel_handler != handler)
ret = -EINVAL;
if (!ret)
xfrm6_tunnel_handler = NULL;
up(&xfrm6_tunnel_sem);
synchronize_net();
return ret;
}
EXPORT_SYMBOL(xfrm6_tunnel_deregister);
static int xfrm6_tunnel_rcv(struct sk_buff **pskb)
{
struct sk_buff *skb = *pskb;
struct xfrm6_tunnel *handler = xfrm6_tunnel_handler;
struct ipv6hdr *iph = skb->nh.ipv6h;
u32 spi;
/* device-like_ip6ip6_handler() */
if (handler && handler->handler(pskb) == 0)
return 0;
spi = xfrm6_tunnel_spi_lookup((xfrm_address_t *)&iph->saddr);
return xfrm6_rcv_spi(pskb, spi);
}
static void xfrm6_tunnel_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
int type, int code, int offset, __u32 info)
{
struct xfrm6_tunnel *handler = xfrm6_tunnel_handler;
/* call here first for device-like ip6ip6 err handling */
if (handler) {
handler->err_handler(skb, opt, type, code, offset, info);
return;
}
/* 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;
}
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 inet6_protocol xfrm6_tunnel_protocol = {
.handler = xfrm6_tunnel_rcv,
.err_handler = xfrm6_tunnel_err,
.flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
};
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 (inet6_add_protocol(&xfrm6_tunnel_protocol, IPPROTO_IPV6) < 0) {
X6TPRINTK1(KERN_ERR
"xfrm6_tunnel init(): can't add protocol\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");
inet6_del_protocol(&xfrm6_tunnel_protocol, IPPROTO_IPV6);
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 (inet6_del_protocol(&xfrm6_tunnel_protocol, IPPROTO_IPV6) < 0)
X6TPRINTK1(KERN_ERR
"xfrm6_tunnel close: can't remove protocol\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");