Function bstp_reinit

freebsd/net/bridgestp.c:2021–2109

}

void
bstp_reinit(struct bstp_state *bs)
{
	struct epoch_tracker et;
	struct bstp_port *bp;
	struct ifnet *ifp, *mif;
	u_char *e_addr;
	void *bridgeptr;
	static const u_char llzero[ETHER_ADDR_LEN];	/* 00:00:00:00:00:00 */

	BSTP_LOCK_ASSERT(bs);

	if (LIST_EMPTY(&bs->bs_bplist))
		goto disablestp;

	mif = NULL;
	bridgeptr = LIST_FIRST(&bs->bs_bplist)->bp_ifp->if_bridge;
	KASSERT(bridgeptr != NULL, ("Invalid bridge pointer"));
	/*
	 * Search through the Ethernet adapters and find the one with the
	 * lowest value. Make sure the adapter which we take the MAC address
	 * from is part of this bridge, so we can have more than one independent
	 * bridges in the same STP domain.
	 */
	NET_EPOCH_ENTER(et);
	CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link) {
		if (ifp->if_type != IFT_ETHER)
			continue;	/* Not Ethernet */

		if (ifp->if_bridge != bridgeptr)
			continue;	/* Not part of our bridge */

		if (bstp_addr_cmp(IF_LLADDR(ifp), llzero) == 0)
			continue;	/* No mac address set */

		if (mif == NULL) {
			mif = ifp;
			continue;
		}
		if (bstp_addr_cmp(IF_LLADDR(ifp), IF_LLADDR(mif)) < 0) {
			mif = ifp;
			continue;
		}
	}
	NET_EPOCH_EXIT(et);
	if (mif == NULL)
		goto disablestp;

	e_addr = IF_LLADDR(mif);
	bs->bs_bridge_pv.pv_dbridge_id =
	    (((uint64_t)bs->bs_bridge_priority) << 48) |
	    (((uint64_t)e_addr[0]) << 40) |
	    (((uint64_t)e_addr[1]) << 32) |
	    (((uint64_t)e_addr[2]) << 24) |
	    (((uint64_t)e_addr[3]) << 16) |
	    (((uint64_t)e_addr[4]) << 8) |
	    (((uint64_t)e_addr[5]));