Declare a new EVENTHANDLER called iflladdr_event which signals that the L2

address on an interface has changed. This lets stacked interfaces such as
vlan(4) detect that their lower interface has changed and adjust things in
order to keep working. Previously this situation broke at least vlan(4) and
lagg(4) configurations.

The EVENTHANDLER_INVOKE call was not placed within if_setlladdr() due to the
risk of a loop.

PR:		kern/142927
Submitted by:	Nikolay Denev

5 files changed, 49 insertions, 0 deletions

diff --git a/sys/net/if.c b/sys/net/if.c
index ad77d65..aa04eff 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -2268,6 +2268,7 @@ ifhwioctl(u_long cmd, struct ifnet *ifp, caddr_t data, struct thread *td)
 			return (error);
 		error = if_setlladdr(ifp,
 		    ifr->ifr_addr.sa_data, ifr->ifr_addr.sa_len);
+		EVENTHANDLER_INVOKE(iflladdr_event, ifp);
 		break;
 
 	case SIOCAIFGROUP:
diff --git a/sys/net/if_bridge.c b/sys/net/if_bridge.c
index 36fb9d8..7084fe6 100644
--- a/sys/net/if_bridge.c
+++ b/sys/net/if_bridge.c
@@ -917,6 +917,7 @@ bridge_delete_member(struct bridge_softc *sc, struct bridge_iflist *bif,
 			    IF_LLADDR(sc->sc_ifp), ETHER_ADDR_LEN);
 			sc->sc_ifaddr = fif;
 		}
+		EVENTHANDLER_INVOKE(iflladdr_event, sc->sc_ifp);
 	}
 
 	bridge_mutecaps(sc);	/* recalcuate now this interface is removed */
@@ -1033,6 +1034,7 @@ bridge_ioctl_add(struct bridge_softc *sc, void *arg)
 	    !memcmp(IF_LLADDR(sc->sc_ifp), sc->sc_defaddr, ETHER_ADDR_LEN)) {
 		bcopy(IF_LLADDR(ifs), IF_LLADDR(sc->sc_ifp), ETHER_ADDR_LEN);
 		sc->sc_ifaddr = ifs;
+		EVENTHANDLER_INVOKE(iflladdr_event, sc->sc_ifp);
 	}
 
 	ifs->if_bridge = sc;
diff --git a/sys/net/if_lagg.c b/sys/net/if_lagg.c
index 0682d43..c017185 100644
--- a/sys/net/if_lagg.c
+++ b/sys/net/if_lagg.c
@@ -305,6 +305,7 @@ lagg_lladdr(struct lagg_softc *sc, uint8_t *lladdr)
 	/* Let the protocol know the MAC has changed */
 	if (sc->sc_lladdr != NULL)
 		(*sc->sc_lladdr)(sc);
+	EVENTHANDLER_INVOKE(iflladdr_event, ifp);
 }
 
 static void
diff --git a/sys/net/if_var.h b/sys/net/if_var.h
index 28b5571..87ad1a2 100644
--- a/sys/net/if_var.h
+++ b/sys/net/if_var.h
@@ -339,6 +339,9 @@ void	if_maddr_runlock(struct ifnet *ifp);	/* if_multiaddrs */
 } while(0)
 
 #ifdef _KERNEL
+/* interface link layer address change event */
+typedef void (*iflladdr_event_handler_t)(void *, struct ifnet *);
+EVENTHANDLER_DECLARE(iflladdr_event, iflladdr_event_handler_t);
 /* interface address change event */
 typedef void (*ifaddr_event_handler_t)(void *, struct ifnet *);
 EVENTHANDLER_DECLARE(ifaddr_event, ifaddr_event_handler_t);
diff --git a/sys/net/if_vlan.c b/sys/net/if_vlan.c
index 6a85956..84edf1b 100644
--- a/sys/net/if_vlan.c
+++ b/sys/net/if_vlan.c
@@ -138,6 +138,7 @@ SYSCTL_INT(_net_link_vlan, OID_AUTO, soft_pad, CTLFLAG_RW, &soft_pad, 0,
 static MALLOC_DEFINE(M_VLAN, VLANNAME, "802.1Q Virtual LAN Interface");
 
 static eventhandler_tag ifdetach_tag;
+static eventhandler_tag iflladdr_tag;
 
 /*
  * We have a global mutex, that is used to serialize configuration
@@ -199,6 +200,7 @@ static	int vlan_clone_create(struct if_clone *, char *, size_t, caddr_t);
 static	int vlan_clone_destroy(struct if_clone *, struct ifnet *);
 
 static	void vlan_ifdetach(void *arg, struct ifnet *ifp);
+static  void vlan_iflladdr(void *arg, struct ifnet *ifp);
 
 static	struct if_clone vlan_cloner = IFC_CLONE_INITIALIZER(VLANNAME, NULL,
     IF_MAXUNIT, NULL, vlan_clone_match, vlan_clone_create, vlan_clone_destroy);
@@ -463,6 +465,41 @@ vlan_setmulti(struct ifnet *ifp)
 }
 
 /*
+ * A handler for parent interface link layer address changes.
+ * If the parent interface link layer address is changed we
+ * should also change it on all children vlans.
+ */
+static void
+vlan_iflladdr(void *arg __unused, struct ifnet *ifp)
+{
+	struct ifvlan *ifv;
+	int i;
+
+	/*
+	 * Check if it's a trunk interface first of all
+	 * to avoid needless locking.
+	 */
+	if (ifp->if_vlantrunk == NULL)
+		return;
+
+	VLAN_LOCK();
+	/*
+	 * OK, it's a trunk.  Loop over and change all vlan's lladdrs on it.
+	 */
+#ifdef VLAN_ARRAY
+	for (i = 0; i < VLAN_ARRAY_SIZE; i++)
+		if ((ifv = ifp->if_vlantrunk->vlans[i]))
+			if_setlladdr(ifv->ifv_ifp, IF_LLADDR(ifp), ETHER_ADDR_LEN);
+#else /* VLAN_ARRAY */
+	for (i = 0; i < (1 << ifp->if_vlantrunk->hwidth); i++)
+		LIST_FOREACH(ifv, &ifp->if_vlantrunk->hash[i], ifv_list)
+			if_setlladdr(ifv->ifv_ifp, IF_LLADDR(ifp), ETHER_ADDR_LEN);
+#endif /* VLAN_ARRAY */
+	VLAN_UNLOCK();
+
+}
+
+/*
  * A handler for network interface departure events.
  * Track departure of trunks here so that we don't access invalid
  * pointers or whatever if a trunk is ripped from under us, e.g.,
@@ -537,6 +574,10 @@ vlan_modevent(module_t mod, int type, void *data)
 		    vlan_ifdetach, NULL, EVENTHANDLER_PRI_ANY);
 		if (ifdetach_tag == NULL)
 			return (ENOMEM);
+		iflladdr_tag = EVENTHANDLER_REGISTER(iflladdr_event,
+		    vlan_iflladdr, NULL, EVENTHANDLER_PRI_ANY);
+		if (iflladdr_tag == NULL)
+			return (ENOMEM);
 		VLAN_LOCK_INIT();
 		vlan_input_p = vlan_input;
 		vlan_link_state_p = vlan_link_state;
@@ -555,6 +596,7 @@ vlan_modevent(module_t mod, int type, void *data)
 	case MOD_UNLOAD:
 		if_clone_detach(&vlan_cloner);
 		EVENTHANDLER_DEREGISTER(ifnet_departure_event, ifdetach_tag);
+		EVENTHANDLER_DEREGISTER(iflladdr_event, iflladdr_tag);
 		vlan_input_p = NULL;
 		vlan_link_state_p = NULL;
 		vlan_trunk_cap_p = NULL;