security: remove the security_netlink_recv hook as it is equivalent to capable()
[linux-2.6.git] / net / ipv6 / xfrm6_tunnel.c
index 80193db..4fe1db1 100644 (file)
  */
 #include <linux/module.h>
 #include <linux/xfrm.h>
-#include <linux/list.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 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_RWLOCK(xfrm6_tunnel_spi_lock);
-
-static u32 xfrm6_tunnel_spi;
-
-#define XFRM6_TUNNEL_SPI_MIN   1
-#define XFRM6_TUNNEL_SPI_MAX   0xffffffff
+static DEFINE_SPINLOCK(xfrm6_tunnel_spi_lock);
 
 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)
+static inline unsigned xfrm6_tunnel_spi_hash_byaddr(const xfrm_address_t *addr)
 {
        unsigned h;
 
@@ -75,49 +85,14 @@ 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)
+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;
        struct hlist_node *pos;
 
-       hlist_for_each_entry(x6spi, pos,
-                            &xfrm6_tunnel_spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
+       hlist_for_each_entry_rcu(x6spi, pos,
+                            &xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
                             list_byaddr) {
                if (memcmp(&x6spi->addr, saddr, sizeof(x6spi->addr)) == 0)
                        return x6spi;
@@ -126,28 +101,29 @@ static struct xfrm6_tunnel_spi *__xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr)
        return NULL;
 }
 
-__be32 xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr)
+__be32 xfrm6_tunnel_spi_lookup(struct net *net, const xfrm_address_t *saddr)
 {
        struct xfrm6_tunnel_spi *x6spi;
        u32 spi;
 
-       read_lock_bh(&xfrm6_tunnel_spi_lock);
-       x6spi = __xfrm6_tunnel_spi_lookup(saddr);
+       rcu_read_lock_bh();
+       x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
        spi = x6spi ? x6spi->spi : 0;
-       read_unlock_bh(&xfrm6_tunnel_spi_lock);
+       rcu_read_unlock_bh();
        return htonl(spi);
 }
 
 EXPORT_SYMBOL(xfrm6_tunnel_spi_lookup);
 
-static int __xfrm6_tunnel_spi_check(u32 spi)
+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);
        struct hlist_node *pos;
 
        hlist_for_each_entry(x6spi, pos,
-                            &xfrm6_tunnel_spi_byspi[index],
+                            &xfrm6_tn->spi_byspi[index],
                             list_byspi) {
                if (x6spi->spi == spi)
                        return -1;
@@ -155,32 +131,33 @@ static int __xfrm6_tunnel_spi_check(u32 spi)
        return index;
 }
 
-static u32 __xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr)
+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_tunnel_spi < XFRM6_TUNNEL_SPI_MIN ||
-           xfrm6_tunnel_spi >= XFRM6_TUNNEL_SPI_MAX)
-               xfrm6_tunnel_spi = XFRM6_TUNNEL_SPI_MIN;
+       if (xfrm6_tn->spi < XFRM6_TUNNEL_SPI_MIN ||
+           xfrm6_tn->spi >= XFRM6_TUNNEL_SPI_MAX)
+               xfrm6_tn->spi = XFRM6_TUNNEL_SPI_MIN;
        else
-               xfrm6_tunnel_spi++;
+               xfrm6_tn->spi++;
 
-       for (spi = xfrm6_tunnel_spi; spi <= XFRM6_TUNNEL_SPI_MAX; spi++) {
-               index = __xfrm6_tunnel_spi_check(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_tunnel_spi; spi++) {
-               index = __xfrm6_tunnel_spi_check(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_tunnel_spi = spi;
+       xfrm6_tn->spi = spi;
        x6spi = kmem_cache_alloc(xfrm6_tunnel_spi_kmem, GFP_ATOMIC);
        if (!x6spi)
                goto out;
@@ -189,58 +166,63 @@ alloc_spi:
        x6spi->spi = spi;
        atomic_set(&x6spi->refcnt, 1);
 
-       hlist_add_head(&x6spi->list_byspi, &xfrm6_tunnel_spi_byspi[index]);
+       hlist_add_head_rcu(&x6spi->list_byspi, &xfrm6_tn->spi_byspi[index]);
 
        index = xfrm6_tunnel_spi_hash_byaddr(saddr);
-       hlist_add_head(&x6spi->list_byaddr, &xfrm6_tunnel_spi_byaddr[index]);
+       hlist_add_head_rcu(&x6spi->list_byaddr, &xfrm6_tn->spi_byaddr[index]);
 out:
        return spi;
 }
 
-__be32 xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr)
+__be32 xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr)
 {
        struct xfrm6_tunnel_spi *x6spi;
        u32 spi;
 
-       write_lock_bh(&xfrm6_tunnel_spi_lock);
-       x6spi = __xfrm6_tunnel_spi_lookup(saddr);
+       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(saddr);
-       write_unlock_bh(&xfrm6_tunnel_spi_lock);
+               spi = __xfrm6_tunnel_alloc_spi(net, saddr);
+       spin_unlock_bh(&xfrm6_tunnel_spi_lock);
 
        return htonl(spi);
 }
 
 EXPORT_SYMBOL(xfrm6_tunnel_alloc_spi);
 
-void xfrm6_tunnel_free_spi(xfrm_address_t *saddr)
+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 *pos, *n;
 
-       write_lock_bh(&xfrm6_tunnel_spi_lock);
+       spin_lock_bh(&xfrm6_tunnel_spi_lock);
 
        hlist_for_each_entry_safe(x6spi, pos, n,
-                                 &xfrm6_tunnel_spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
+                                 &xfrm6_tn->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);
+                               hlist_del_rcu(&x6spi->list_byaddr);
+                               hlist_del_rcu(&x6spi->list_byspi);
+                               call_rcu(&x6spi->rcu_head, x6spi_destroy_rcu);
                                break;
                        }
                }
        }
-       write_unlock_bh(&xfrm6_tunnel_spi_lock);
+       spin_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));
@@ -254,15 +236,16 @@ static int xfrm6_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
 
 static int xfrm6_tunnel_rcv(struct sk_buff *skb)
 {
-       struct ipv6hdr *iph = ipv6_hdr(skb);
+       struct net *net = dev_net(skb->dev);
+       const 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;
+       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,
-                           int type, int code, int offset, __be32 info)
+                           u8 type, u8 code, int offset, __be32 info)
 {
        /* xfrm6_tunnel native err handling */
        switch (type) {
@@ -317,7 +300,9 @@ static int xfrm6_tunnel_init_state(struct xfrm_state *x)
 
 static void xfrm6_tunnel_destroy(struct xfrm_state *x)
 {
-       xfrm6_tunnel_free_spi((xfrm_address_t *)&x->props.saddr);
+       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 = {
@@ -330,46 +315,85 @@ static const struct xfrm_type xfrm6_tunnel_type = {
        .output         = xfrm6_tunnel_output,
 };
 
-static struct xfrm6_tunnel xfrm6_tunnel_handler = {
+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 = {
+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)
 {
-       if (xfrm_register_type(&xfrm6_tunnel_type, AF_INET6) < 0)
-               goto err;
-       if (xfrm6_tunnel_register(&xfrm6_tunnel_handler, AF_INET6))
-               goto unreg;
-       if (xfrm6_tunnel_register(&xfrm46_tunnel_handler, AF_INET))
-               goto dereg6;
-       if (xfrm6_tunnel_spi_init() < 0)
-               goto dereg46;
+       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;
 
-dereg46:
-       xfrm6_tunnel_deregister(&xfrm46_tunnel_handler, AF_INET);
-dereg6:
+out_xfrm46:
        xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
-unreg:
+out_xfrm6:
        xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
-err:
-       return -EAGAIN;
+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_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);
+       unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
+       kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
 }
 
 module_init(xfrm6_tunnel_init);