net/ipv6/addrconf_core.c

   1 /*
   2  * IPv6 library code, needed by static components when full IPv6 support is
   3  * not configured or static.
   4  */
   5
   6 #include <linux/export.h>
   7 #include <net/ipv6.h>
   8 #include <net/addrconf.h>
   9
  10 #define IPV6_ADDR_SCOPE_TYPE(scope)     ((scope) << 16)
  11
  12 static inline unsigned int ipv6_addr_scope2type(unsigned int scope)
  13 {
  14         switch (scope) {
  15         case IPV6_ADDR_SCOPE_NODELOCAL:
  16                 return (IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_NODELOCAL) |
  17                         IPV6_ADDR_LOOPBACK);
  18         case IPV6_ADDR_SCOPE_LINKLOCAL:
  19                 return (IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_LINKLOCAL) |
  20                         IPV6_ADDR_LINKLOCAL);
  21         case IPV6_ADDR_SCOPE_SITELOCAL:
  22                 return (IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_SITELOCAL) |
  23                         IPV6_ADDR_SITELOCAL);
  24         }
  25         return IPV6_ADDR_SCOPE_TYPE(scope);
  26 }
  27
  28 int __ipv6_addr_type(const struct in6_addr *addr)
  29 {
  30         __be32 st;
  31
  32         st = addr->s6_addr32[0];
  33
  34         /* Consider all addresses with the first three bits different of
  35            000 and 111 as unicasts.
  36          */
  37         if ((st & htonl(0xE0000000)) != htonl(0x00000000) &&
  38             (st & htonl(0xE0000000)) != htonl(0xE0000000))
  39                 return (IPV6_ADDR_UNICAST |
  40                         IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL));
  41
  42         if ((st & htonl(0xFF000000)) == htonl(0xFF000000)) {
  43                 /* multicast */
  44                 /* addr-select 3.1 */
  45                 return (IPV6_ADDR_MULTICAST |
  46                         ipv6_addr_scope2type(IPV6_ADDR_MC_SCOPE(addr)));
  47         }
  48
  49         if ((st & htonl(0xFFC00000)) == htonl(0xFE800000))
  50                 return (IPV6_ADDR_LINKLOCAL | IPV6_ADDR_UNICAST |
  51                         IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_LINKLOCAL));               /* addr-select 3.1 */
  52         if ((st & htonl(0xFFC00000)) == htonl(0xFEC00000))
  53                 return (IPV6_ADDR_SITELOCAL | IPV6_ADDR_UNICAST |
  54                         IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_SITELOCAL));               /* addr-select 3.1 */
  55         if ((st & htonl(0xFE000000)) == htonl(0xFC000000))
  56                 return (IPV6_ADDR_UNICAST |
  57                         IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL));                  /* RFC 4193 */
  58
  59         if ((addr->s6_addr32[0] | addr->s6_addr32[1]) == 0) {
  60                 if (addr->s6_addr32[2] == 0) {
  61                         if (addr->s6_addr32[3] == 0)
  62                                 return IPV6_ADDR_ANY;
  63
  64                         if (addr->s6_addr32[3] == htonl(0x00000001))
  65                                 return (IPV6_ADDR_LOOPBACK | IPV6_ADDR_UNICAST |
  66                                         IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_LINKLOCAL));       /* addr-select 3.4 */
  67
  68                         return (IPV6_ADDR_COMPATv4 | IPV6_ADDR_UNICAST |
  69                                 IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL));  /* addr-select 3.3 */
  70                 }
  71
  72                 if (addr->s6_addr32[2] == htonl(0x0000ffff))
  73                         return (IPV6_ADDR_MAPPED |
  74                                 IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL));  /* addr-select 3.3 */
  75         }
  76
  77         return (IPV6_ADDR_UNICAST |
  78                 IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL));  /* addr-select 3.4 */
  79 }
  80 EXPORT_SYMBOL(__ipv6_addr_type);
  81
  82 static ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
  83
  84 int register_inet6addr_notifier(struct notifier_block *nb)
  85 {
  86         return atomic_notifier_chain_register(&inet6addr_chain, nb);
  87 }
  88 EXPORT_SYMBOL(register_inet6addr_notifier);
  89
  90 int unregister_inet6addr_notifier(struct notifier_block *nb)
  91 {
  92         return atomic_notifier_chain_unregister(&inet6addr_chain, nb);
  93 }
  94 EXPORT_SYMBOL(unregister_inet6addr_notifier);
  95
  96 int inet6addr_notifier_call_chain(unsigned long val, void *v)
  97 {
  98         return atomic_notifier_call_chain(&inet6addr_chain, val, v);
  99 }
 100 EXPORT_SYMBOL(inet6addr_notifier_call_chain);
 101
 102 const struct ipv6_stub *ipv6_stub __read_mostly;
 103 EXPORT_SYMBOL_GPL(ipv6_stub);