diff options
| -rw-r--r-- | sys/net/if_bridge.c | 27 |
1 files changed, 21 insertions, 6 deletions
diff --git a/sys/net/if_bridge.c b/sys/net/if_bridge.c index d230238..caf24af 100644 --- a/sys/net/if_bridge.c +++ b/sys/net/if_bridge.c @@ -450,9 +450,10 @@ SYSCTL_PROC(_net_link_bridge, OID_AUTO, ipfw, CTLTYPE_INT|CTLFLAG_RW, static int bridge_clone_create(struct if_clone *ifc, int unit) { - struct bridge_softc *sc; - struct ifnet *ifp; + struct bridge_softc *sc, *sc2; + struct ifnet *bifp, *ifp; u_char eaddr[6]; + int retry; sc = malloc(sizeof(*sc), M_DEVBUF, M_WAITOK|M_ZERO); BRIDGE_LOCK_INIT(sc); @@ -496,11 +497,25 @@ bridge_clone_create(struct if_clone *ifc, int unit) /* * Generate a random ethernet address and use the private AC:DE:48 * OUI code. + * + * Since we are using random ethernet addresses for the bridge, it is + * possible that we might have address collisions, so make sure that + * this hardware address isn't already in use on another bridge. */ - arc4rand(eaddr, ETHER_ADDR_LEN, 1); - eaddr[0] = 0xAC; - eaddr[1] = 0xDE; - eaddr[2] = 0x48; + for (retry = 1; retry != 0;) { + arc4rand(eaddr, ETHER_ADDR_LEN, 1); + eaddr[0] = 0xAC; + eaddr[1] = 0xDE; + eaddr[2] = 0x48; + retry = 0; + mtx_lock(&bridge_list_mtx); + LIST_FOREACH(sc2, &bridge_list, sc_list) { + bifp = sc2->sc_ifp; + if (memcmp(eaddr, IF_LLADDR(bifp), ETHER_ADDR_LEN) == 0) + retry = 1; + } + mtx_unlock(&bridge_list_mtx); + } ether_ifattach(ifp, eaddr); /* Now undo some of the damage... */ |
