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