root/net/ipv6/addrconf_core.c

DEFINITIONS

1. ipv6_addr_scope2type
2. __ipv6_addr_type

/*
 * IPv6 library code, needed by static components when full IPv6 support is
 * not configured or static.
 */

#include <net/ipv6.h>

#define IPV6_ADDR_SCOPE_TYPE(scope)     ((scope) << 16)

static inline unsigned ipv6_addr_scope2type(unsigned scope)
{
        switch(scope) {
        case IPV6_ADDR_SCOPE_NODELOCAL:
                return (IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_NODELOCAL) |
                        IPV6_ADDR_LOOPBACK);
        case IPV6_ADDR_SCOPE_LINKLOCAL:
                return (IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_LINKLOCAL) |
                        IPV6_ADDR_LINKLOCAL);
        case IPV6_ADDR_SCOPE_SITELOCAL:
                return (IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_SITELOCAL) |
                        IPV6_ADDR_SITELOCAL);
        }
        return IPV6_ADDR_SCOPE_TYPE(scope);
}

int __ipv6_addr_type(const struct in6_addr *addr)
{
        __be32 st;

        st = addr->s6_addr32[0];

        /* Consider all addresses with the first three bits different of
           000 and 111 as unicasts.
         */
        if ((st & htonl(0xE0000000)) != htonl(0x00000000) &&
            (st & htonl(0xE0000000)) != htonl(0xE0000000))
                return (IPV6_ADDR_UNICAST |
                        IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL));

        if ((st & htonl(0xFF000000)) == htonl(0xFF000000)) {
                /* multicast */
                /* addr-select 3.1 */
                return (IPV6_ADDR_MULTICAST |
                        ipv6_addr_scope2type(IPV6_ADDR_MC_SCOPE(addr)));
        }

        if ((st & htonl(0xFFC00000)) == htonl(0xFE800000))
                return (IPV6_ADDR_LINKLOCAL | IPV6_ADDR_UNICAST |
                        IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_LINKLOCAL));               /* addr-select 3.1 */
        if ((st & htonl(0xFFC00000)) == htonl(0xFEC00000))
                return (IPV6_ADDR_SITELOCAL | IPV6_ADDR_UNICAST |
                        IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_SITELOCAL));               /* addr-select 3.1 */
        if ((st & htonl(0xFE000000)) == htonl(0xFC000000))
                return (IPV6_ADDR_UNICAST |
                        IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL));                  /* RFC 4193 */

        if ((addr->s6_addr32[0] | addr->s6_addr32[1]) == 0) {
                if (addr->s6_addr32[2] == 0) {
                        if (addr->s6_addr32[3] == 0)
                                return IPV6_ADDR_ANY;

                        if (addr->s6_addr32[3] == htonl(0x00000001))
                                return (IPV6_ADDR_LOOPBACK | IPV6_ADDR_UNICAST |
                                        IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_LINKLOCAL));       /* addr-select 3.4 */

                        return (IPV6_ADDR_COMPATv4 | IPV6_ADDR_UNICAST |
                                IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL));  /* addr-select 3.3 */
                }

                if (addr->s6_addr32[2] == htonl(0x0000ffff))
                        return (IPV6_ADDR_MAPPED |
                                IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL));  /* addr-select 3.3 */
        }

        return (IPV6_ADDR_RESERVED |
                IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL));  /* addr-select 3.4 */
}
EXPORT_SYMBOL(__ipv6_addr_type);