diff options
Diffstat (limited to 'kernel/net/ipv6/xfrm6_tunnel.c')
-rw-r--r-- | kernel/net/ipv6/xfrm6_tunnel.c | 397 |
1 files changed, 397 insertions, 0 deletions
diff --git a/kernel/net/ipv6/xfrm6_tunnel.c b/kernel/net/ipv6/xfrm6_tunnel.c new file mode 100644 index 000000000..5743044cd --- /dev/null +++ b/kernel/net/ipv6/xfrm6_tunnel.c @@ -0,0 +1,397 @@ +/* + * 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); |