ipv6: introdcue __ipv6_addr_needs_scope_id and ipv6_iface_scope_id helper functions
Hannes Frederic Sowa [Fri, 8 Mar 2013 02:07:16 +0000 (02:07 +0000)]
[net-next commit b7ef213ef65256168df83ddfbb8131ed9adc10f9]

__ipv6_addr_needs_scope_id checks if an ipv6 address needs to supply
a 'sin6_scope_id != 0'. 'sin6_scope_id != 0' was enforced in case
of link-local addresses. To support interface-local multicast these
checks had to be enhanced and are now consolidated into these new helper
functions.

v2:
a) migrated to struct ipv6_addr_props

v3:
a) reverted changes for ipv6_addr_props
b) test for address type instead of comparing scope

v4:
a) unchanged

Bug 1412141

Change-Id: I1788f1f2d3a6bd2b9e6a6afe74992d6d4a1385eb
Suggested-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 2c75b248e5243d0af7cc97522148db7415a70f8a)
Reviewed-on: http://git-master/r/336266
(cherry picked from commit dfd23e75d7f69863ec3903ea1300185a1474b56a)
Reviewed-on: http://git-master/r/353229
Reviewed-by: Nitin Bindal <nbindal@nvidia.com>
Tested-by: Nitin Bindal <nbindal@nvidia.com>
Reviewed-by: Bitan Biswas <bbiswas@nvidia.com>
Reviewed-by: Gabby Lee <galee@nvidia.com>

include/net/ipv6.h

index 12a1bd2..155a84a 100644 (file)
@@ -295,6 +295,18 @@ static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
        return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
 }
 
+static inline bool __ipv6_addr_needs_scope_id(int type)
+{
+       return type & IPV6_ADDR_LINKLOCAL ||
+              (type & IPV6_ADDR_MULTICAST &&
+               (type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
+}
+
+static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
+{
+       return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
+}
+
 static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
 {
        return memcmp(a1, a2, sizeof(struct in6_addr));