- Allow ND6_IFF_AUTO_LINKLOCAL for IFT_BRIDGE. An interface with IFT_BRIDGE

  is initialized with !ND6_IFF_AUTO_LINKLOCAL && !ND6_IFF_ACCEPT_RTADV
  regardless of net.inet6.ip6.accept_rtadv and net.inet6.ip6.auto_linklocal.
  To configure an autoconfigured link-local address (RFC 4862), the
  following rc.conf(5) configuration can be used:

   ifconfig_bridge0_ipv6="inet6 auto_linklocal"

- if_bridge(4) now removes IPv6 addresses on a member interface to be
  added when the parent interface or one of the existing member
  interfaces has an IPv6 address.  if_bridge(4) merges each link-local
  scope zone which the member interfaces form respectively, so it causes
  address scope violation.  Removal of the IPv6 addresses prevents it.

- if_lagg(4) now removes IPv6 addresses on a member interfaces
  unconditionally.

- Set reasonable flags to non-IPv6-capable interfaces. [*]

Submitted by:	rpaulo [*]
MFC after:	1 week

1 files changed, 26 insertions, 0 deletions

diff --git a/sys/netinet6/in6.c b/sys/netinet6/in6.c
index 80359c1..9e005c5 100644
--- a/sys/netinet6/in6.c
+++ b/sys/netinet6/in6.c
@@ -1987,6 +1987,32 @@ in6ifa_ifpwithaddr(struct ifnet *ifp, struct in6_addr *addr)
 }
 
 /*
+ * Find a link-local scoped address on ifp and return it if any.
+ */
+struct in6_ifaddr *
+in6ifa_llaonifp(struct ifnet *ifp)
+{
+	struct sockaddr_in6 *sin6;
+	struct ifaddr *ifa;
+
+	if (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)
+		return (NULL);
+	if_addr_rlock(ifp);
+	TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
+		if (ifa->ifa_addr->sa_family != AF_INET6)
+			continue;
+		sin6 = (struct sockaddr_in6 *)ifa->ifa_addr;
+		if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) ||
+		    IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr) ||
+		    IN6_IS_ADDR_MC_NODELOCAL(&sin6->sin6_addr))
+			break;
+	}
+	if_addr_runlock(ifp);
+
+	return ((struct in6_ifaddr *)ifa);
+}
+
+/*
  * Convert IP6 address to printable (loggable) representation. Caller
  * has to make sure that ip6buf is at least INET6_ADDRSTRLEN long.
  */