- 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, 30 insertions, 0 deletions

diff --git a/sys/net/if_lagg.c b/sys/net/if_lagg.c
index 11273b2..9867c97 100644
--- a/sys/net/if_lagg.c
+++ b/sys/net/if_lagg.c
@@ -63,6 +63,8 @@ __FBSDID("$FreeBSD$");
 
 #ifdef INET6
 #include <netinet/ip6.h>
+#include <netinet6/in6_var.h>
+#include <netinet6/in6_ifattach.h>
 #endif
 
 #include <net/if_vlan_var.h>
@@ -543,6 +545,34 @@ lagg_port_create(struct lagg_softc *sc, struct ifnet *ifp)
 	if (ifp->if_type != IFT_ETHER)
 		return (EPROTONOSUPPORT);
 
+#ifdef INET6
+	/*
+	 * The member interface should not have inet6 address because
+	 * two interfaces with a valid link-local scope zone must not be
+	 * merged in any form.  This restriction is needed to
+	 * prevent violation of link-local scope zone.  Attempts to
+	 * add a member interface which has inet6 addresses triggers
+	 * removal of all inet6 addresses on the member interface.
+	 */
+	SLIST_FOREACH(lp, &sc->sc_ports, lp_entries) {
+		if (in6ifa_llaonifp(lp->lp_ifp)) {
+			in6_ifdetach(lp->lp_ifp);
+			if_printf(sc->sc_ifp,
+			    "IPv6 addresses on %s have been removed "
+			    "before adding it as a member to prevent "
+			    "IPv6 address scope violation.\n",
+			    lp->lp_ifp->if_xname);
+		}
+	}
+	if (in6ifa_llaonifp(ifp)) {
+		in6_ifdetach(ifp);
+		if_printf(sc->sc_ifp,
+		    "IPv6 addresses on %s have been removed "
+		    "before adding it as a member to prevent "
+		    "IPv6 address scope violation.\n",
+		    ifp->if_xname);
+	}
+#endif
 	/* Allow the first Ethernet member to define the MTU */
 	if (SLIST_EMPTY(&sc->sc_ports))
 		sc->sc_ifp->if_mtu = ifp->if_mtu;