Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / net / ipv6 / xfrm6_tunnel.c
diff --git a/kernel/net/ipv6/xfrm6_tunnel.c b/kernel/net/ipv6/xfrm6_tunnel.c
new file mode 100644 (file)
index 0000000..5743044
--- /dev/null
@@ -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);