net/ipv6/ip6_icmp.c

   1 #include <linux/export.h>
   2 #include <linux/icmpv6.h>
   3 #include <linux/mutex.h>
   4 #include <linux/netdevice.h>
   5 #include <linux/spinlock.h>
   6
   7 #include <net/ipv6.h>
   8
   9 #if IS_ENABLED(CONFIG_IPV6)
  10
  11 static ip6_icmp_send_t __rcu *ip6_icmp_send;
  12
  13 int inet6_register_icmp_sender(ip6_icmp_send_t *fn)
  14 {
  15         return (cmpxchg((ip6_icmp_send_t **)&ip6_icmp_send, NULL, fn) == NULL) ?
  16                 0 : -EBUSY;
  17 }
  18 EXPORT_SYMBOL(inet6_register_icmp_sender);
  19
  20 int inet6_unregister_icmp_sender(ip6_icmp_send_t *fn)
  21 {
  22         int ret;
  23
  24         ret = (cmpxchg((ip6_icmp_send_t **)&ip6_icmp_send, fn, NULL) == fn) ?
  25               0 : -EINVAL;
  26
  27         synchronize_net();
  28
  29         return ret;
  30 }
  31 EXPORT_SYMBOL(inet6_unregister_icmp_sender);
  32
  33 void icmpv6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info)
  34 {
  35         ip6_icmp_send_t *send;
  36
  37         rcu_read_lock();
  38         send = rcu_dereference(ip6_icmp_send);
  39
  40         if (!send)
  41                 goto out;
  42         send(skb, type, code, info, NULL);
  43 out:
  44         rcu_read_unlock();
  45 }
  46 EXPORT_SYMBOL(icmpv6_send);
  47 #endif