LXR linux/net/ipv6/addrconf

   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#include <net/ip.h>
  10
  11/* if ipv6 module registers this function is used by xfrm to force all
  12 * sockets to relookup their nodes - this is fairly expensive, be
  13 * careful
  14 */
  15void (*__fib6_flush_trees)(struct net *);
  16EXPORT_SYMBOL(__fib6_flush_trees);
  17
  18#define IPV6_ADDR_SCOPE_TYPE(scope)     ((scope) << 16)
  19
  20static inline unsigned int ipv6_addr_scope2type(unsigned int scope)
  21{
  22        switch (scope) {
  23        case IPV6_ADDR_SCOPE_NODELOCAL:
  24                return (IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_NODELOCAL) |
  25                        IPV6_ADDR_LOOPBACK);
  26        case IPV6_ADDR_SCOPE_LINKLOCAL:
  27                return (IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_LINKLOCAL) |
  28                        IPV6_ADDR_LINKLOCAL);
  29        case IPV6_ADDR_SCOPE_SITELOCAL:
  30                return (IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_SITELOCAL) |
  31                        IPV6_ADDR_SITELOCAL);
  32        }
  33        return IPV6_ADDR_SCOPE_TYPE(scope);
  34}
  35
  36int __ipv6_addr_type(const struct in6_addr *addr)
  37{
  38        __be32 st;
  39
  40        st = addr->s6_addr32[0];
  41
  42        /* Consider all addresses with the first three bits different of
  43           000 and 111 as unicasts.
  44         */
  45        if ((st & htonl(0xE0000000)) != htonl(0x00000000) &&
  46            (st & htonl(0xE0000000)) != htonl(0xE0000000))
  47                return (IPV6_ADDR_UNICAST |
  48                        IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL));
  49
  50        if ((st & htonl(0xFF000000)) == htonl(0xFF000000)) {
  51                /* multicast */
  52                /* addr-select 3.1 */
  53                return (IPV6_ADDR_MULTICAST |
  54                        ipv6_addr_scope2type(IPV6_ADDR_MC_SCOPE(addr)));
  55        }
  56
  57        if ((st & htonl(0xFFC00000)) == htonl(0xFE800000))
  58                return (IPV6_ADDR_LINKLOCAL | IPV6_ADDR_UNICAST |
  59                        IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_LINKLOCAL));               /* addr-select 3.1 */
  60        if ((st & htonl(0xFFC00000)) == htonl(0xFEC00000))
  61                return (IPV6_ADDR_SITELOCAL | IPV6_ADDR_UNICAST |
  62                        IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_SITELOCAL));               /* addr-select 3.1 */
  63        if ((st & htonl(0xFE000000)) == htonl(0xFC000000))
  64                return (IPV6_ADDR_UNICAST |
  65                        IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL));                  /* RFC 4193 */
  66
  67        if ((addr->s6_addr32[0] | addr->s6_addr32[1]) == 0) {
  68                if (addr->s6_addr32[2] == 0) {
  69                        if (addr->s6_addr32[3] == 0)
  70                                return IPV6_ADDR_ANY;
  71
  72                        if (addr->s6_addr32[3] == htonl(0x00000001))
  73                                return (IPV6_ADDR_LOOPBACK | IPV6_ADDR_UNICAST |
  74                                        IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_LINKLOCAL));       /* addr-select 3.4 */
  75
  76                        return (IPV6_ADDR_COMPATv4 | IPV6_ADDR_UNICAST |
  77                                IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL));  /* addr-select 3.3 */
  78                }
  79
  80                if (addr->s6_addr32[2] == htonl(0x0000ffff))
  81                        return (IPV6_ADDR_MAPPED |
  82                                IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL));  /* addr-select 3.3 */
  83        }
  84
  85        return (IPV6_ADDR_UNICAST |
  86                IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL));  /* addr-select 3.4 */
  87}
  88EXPORT_SYMBOL(__ipv6_addr_type);
  89
  90static ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
  91
  92int register_inet6addr_notifier(struct notifier_block *nb)
  93{
  94        return atomic_notifier_chain_register(&inet6addr_chain, nb);
  95}
  96EXPORT_SYMBOL(register_inet6addr_notifier);
  97
  98int unregister_inet6addr_notifier(struct notifier_block *nb)
  99{
 100        return atomic_notifier_chain_unregister(&inet6addr_chain, nb);
 101}
 102EXPORT_SYMBOL(unregister_inet6addr_notifier);
 103
 104int inet6addr_notifier_call_chain(unsigned long val, void *v)
 105{
 106        return atomic_notifier_call_chain(&inet6addr_chain, val, v);
 107}
 108EXPORT_SYMBOL(inet6addr_notifier_call_chain);
 109
 110static int eafnosupport_ipv6_dst_lookup(struct net *net, struct sock *u1,
 111                                        struct dst_entry **u2,
 112                                        struct flowi6 *u3)
 113{
 114        return -EAFNOSUPPORT;
 115}
 116
 117const struct ipv6_stub *ipv6_stub __read_mostly = &(struct ipv6_stub) {
 118        .ipv6_dst_lookup = eafnosupport_ipv6_dst_lookup,
 119};
 120EXPORT_SYMBOL_GPL(ipv6_stub);
 121
 122/* IPv6 Wildcard Address and Loopback Address defined by RFC2553 */
 123const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
 124EXPORT_SYMBOL(in6addr_loopback);
 125const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
 126EXPORT_SYMBOL(in6addr_any);
 127const struct in6_addr in6addr_linklocal_allnodes = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
 128EXPORT_SYMBOL(in6addr_linklocal_allnodes);
 129const struct in6_addr in6addr_linklocal_allrouters = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
 130EXPORT_SYMBOL(in6addr_linklocal_allrouters);
 131const struct in6_addr in6addr_interfacelocal_allnodes = IN6ADDR_INTERFACELOCAL_ALLNODES_INIT;
 132EXPORT_SYMBOL(in6addr_interfacelocal_allnodes);
 133const struct in6_addr in6addr_interfacelocal_allrouters = IN6ADDR_INTERFACELOCAL_ALLROUTERS_INIT;
 134EXPORT_SYMBOL(in6addr_interfacelocal_allrouters);
 135const struct in6_addr in6addr_sitelocal_allrouters = IN6ADDR_SITELOCAL_ALLROUTERS_INIT;
 136EXPORT_SYMBOL(in6addr_sitelocal_allrouters);
 137
 138static void snmp6_free_dev(struct inet6_dev *idev)
 139{
 140        kfree(idev->stats.icmpv6msgdev);
 141        kfree(idev->stats.icmpv6dev);
 142        free_percpu(idev->stats.ipv6);
 143}
 144
 145static void in6_dev_finish_destroy_rcu(struct rcu_head *head)
 146{
 147        struct inet6_dev *idev = container_of(head, struct inet6_dev, rcu);
 148
 149        snmp6_free_dev(idev);
 150        kfree(idev);
 151}
 152
 153/* Nobody refers to this device, we may destroy it. */
 154
 155void in6_dev_finish_destroy(struct inet6_dev *idev)
 156{
 157        struct net_device *dev = idev->dev;
 158
 159        WARN_ON(!list_empty(&idev->addr_list));
 160        WARN_ON(idev->mc_list);
 161        WARN_ON(timer_pending(&idev->rs_timer));
 162
 163#ifdef NET_REFCNT_DEBUG
 164        pr_debug("%s: %s\n", __func__, dev ? dev->name : "NIL");
 165#endif
 166        dev_put(dev);
 167        if (!idev->dead) {
 168                pr_warn("Freeing alive inet6 device %p\n", idev);
 169                return;
 170        }
 171        call_rcu(&idev->rcu, in6_dev_finish_destroy_rcu);
 172}
 173EXPORT_SYMBOL(in6_dev_finish_destroy);
 174