xfrm: Introduce xfrm_input_afinfo to access the the callbacks properly
IPv6 can be build as a module, so we need mechanism to access
the address family dependent callback functions properly.
Therefore we introduce xfrm_input_afinfo, similar to that
what we have for the address family dependent part of
policies and states.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index 4218164..85d1d47 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -16,6 +16,81 @@
static struct kmem_cache *secpath_cachep __read_mostly;
+static DEFINE_SPINLOCK(xfrm_input_afinfo_lock);
+static struct xfrm_input_afinfo __rcu *xfrm_input_afinfo[NPROTO];
+
+int xfrm_input_register_afinfo(struct xfrm_input_afinfo *afinfo)
+{
+ int err = 0;
+
+ if (unlikely(afinfo == NULL))
+ return -EINVAL;
+ if (unlikely(afinfo->family >= NPROTO))
+ return -EAFNOSUPPORT;
+ spin_lock_bh(&xfrm_input_afinfo_lock);
+ if (unlikely(xfrm_input_afinfo[afinfo->family] != NULL))
+ err = -ENOBUFS;
+ else
+ rcu_assign_pointer(xfrm_input_afinfo[afinfo->family], afinfo);
+ spin_unlock_bh(&xfrm_input_afinfo_lock);
+ return err;
+}
+EXPORT_SYMBOL(xfrm_input_register_afinfo);
+
+int xfrm_input_unregister_afinfo(struct xfrm_input_afinfo *afinfo)
+{
+ int err = 0;
+
+ if (unlikely(afinfo == NULL))
+ return -EINVAL;
+ if (unlikely(afinfo->family >= NPROTO))
+ return -EAFNOSUPPORT;
+ spin_lock_bh(&xfrm_input_afinfo_lock);
+ if (likely(xfrm_input_afinfo[afinfo->family] != NULL)) {
+ if (unlikely(xfrm_input_afinfo[afinfo->family] != afinfo))
+ err = -EINVAL;
+ else
+ RCU_INIT_POINTER(xfrm_input_afinfo[afinfo->family], NULL);
+ }
+ spin_unlock_bh(&xfrm_input_afinfo_lock);
+ synchronize_rcu();
+ return err;
+}
+EXPORT_SYMBOL(xfrm_input_unregister_afinfo);
+
+static struct xfrm_input_afinfo *xfrm_input_get_afinfo(unsigned int family)
+{
+ struct xfrm_input_afinfo *afinfo;
+
+ if (unlikely(family >= NPROTO))
+ return NULL;
+ rcu_read_lock();
+ afinfo = rcu_dereference(xfrm_input_afinfo[family]);
+ if (unlikely(!afinfo))
+ rcu_read_unlock();
+ return afinfo;
+}
+
+static void xfrm_input_put_afinfo(struct xfrm_input_afinfo *afinfo)
+{
+ rcu_read_unlock();
+}
+
+static int xfrm_rcv_cb(struct sk_buff *skb, unsigned int family, u8 protocol,
+ int err)
+{
+ int ret;
+ struct xfrm_input_afinfo *afinfo = xfrm_input_get_afinfo(family);
+
+ if (!afinfo)
+ return -EAFNOSUPPORT;
+
+ ret = afinfo->callback(skb, protocol, err);
+ xfrm_input_put_afinfo(afinfo);
+
+ return ret;
+}
+
void __secpath_destroy(struct sec_path *sp)
{
int i;