Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 * 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>

/*

 * 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;

};

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 struct kmem_cache *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];

static inline unsigned xfrm6_tunnel_spi_hash_byaddr(xfrm_address_t *addr)

{

        unsigned h;

        h = (__force u32)(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;

        return h;

}

static inline unsigned xfrm6_tunnel_spi_hash_byspi(u32 spi)

{

        return spi % XFRM6_TUNNEL_SPI_BYSPI_HSIZE;

}

static int xfrm6_tunnel_spi_init(void)

{

        int i;

        xfrm6_tunnel_spi = 0;

        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;

        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;

        for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++) {

                if (!hlist_empty(&xfrm6_tunnel_spi_byaddr[i]))

                        return;

        }

        for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++) {

                if (!hlist_empty(&xfrm6_tunnel_spi_byspi[i]))

                        return;

        }

        kmem_cache_destroy(xfrm6_tunnel_spi_kmem);

        xfrm6_tunnel_spi_kmem = NULL;

}

static struct xfrm6_tunnel_spi *__xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr)

{

        struct xfrm6_tunnel_spi *x6spi;

        struct hlist_node *pos;

        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)

                        return x6spi;

        }

        return NULL;

}

__be32 xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr)

{

        struct xfrm6_tunnel_spi *x6spi;

        u32 spi;

        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 htonl(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;

        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:

        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(&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]);

out:

        return spi;

}

__be32 xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr)

{

        struct xfrm6_tunnel_spi *x6spi;

        u32 spi;

        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);

        return htonl(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;

        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) {

                        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)

{

        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 ipv6hdr *iph = ipv6_hdr(skb);

        __be32 spi;

        spi = xfrm6_tunnel_spi_lookup((xfrm_address_t *)&iph->saddr);

        return xfrm6_rcv_spi(skb, IPPROTO_IPV6, spi) > 0 ? : 0;

}

static int xfrm6_tunnel_err(struct sk_buff *skb, struct inet6_skb_parm *opt,

                            int type, int 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)

{

        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 struct xfrm6_tunnel xfrm46_tunnel_handler = {

        .handler        = xfrm6_tunnel_rcv,

        .err_handler    = xfrm6_tunnel_err,

        .priority       = 2,

};

static int __init xfrm6_tunnel_init(void)

{

        if (xfrm_register_type(&xfrm6_tunnel_type, AF_INET6) < 0)

                return -EAGAIN;

        if (xfrm6_tunnel_register(&xfrm6_tunnel_handler, AF_INET6)) {

                xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);

                return -EAGAIN;

        }

        if (xfrm6_tunnel_register(&xfrm46_tunnel_handler, AF_INET)) {

                xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);

                xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);

                return -EAGAIN;

        }

        if (xfrm6_tunnel_spi_init() < 0) {

                xfrm6_tunnel_deregister(&xfrm46_tunnel_handler, AF_INET);

                xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);

                xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);

                return -EAGAIN;

        }

        return 0;

}

static void __exit xfrm6_tunnel_fini(void)

{

        xfrm6_tunnel_spi_fini();

        xfrm6_tunnel_deregister(&xfrm46_tunnel_handler, AF_INET);

        xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);

        xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);

}

module_init(xfrm6_tunnel_init);

module_exit(xfrm6_tunnel_fini);

MODULE_LICENSE("GPL");

MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_IPV6);