Function ng_iface_constructor

freebsd/netgraph/ng_iface.c:519–572

* Constructor for a node */

 * Constructor for a node
 */
static int
ng_iface_constructor(node_p node)
{
	struct ifnet *ifp;
	priv_p priv;

	/* Allocate node and interface private structures */
	priv = malloc(sizeof(*priv), M_NETGRAPH_IFACE, M_WAITOK | M_ZERO);
	ifp = if_alloc(IFT_PROPVIRTUAL);
	if (ifp == NULL) {
		free(priv, M_NETGRAPH_IFACE);
		return (ENOMEM);
	}

	rm_init(&priv->lock, "ng_iface private rmlock");

	/* Link them together */
	ifp->if_softc = priv;
	priv->ifp = ifp;

	/* Get an interface unit number */
	priv->unit = alloc_unr(V_ng_iface_unit);

	/* Link together node and private info */
	NG_NODE_SET_PRIVATE(node, priv);
	priv->node = node;

	/* Initialize interface structure */
	if_initname(ifp, NG_IFACE_IFACE_NAME, priv->unit);
	ifp->if_output = ng_iface_output;
	ifp->if_start = ng_iface_start;
	ifp->if_ioctl = ng_iface_ioctl;
	ifp->if_mtu = NG_IFACE_MTU_DEFAULT;
	ifp->if_flags = (IFF_SIMPLEX|IFF_POINTOPOINT|IFF_NOARP|IFF_MULTICAST);
	ifp->if_type = IFT_PROPVIRTUAL;		/* XXX */
	ifp->if_addrlen = 0;			/* XXX */
	ifp->if_hdrlen = 0;			/* XXX */
	ifp->if_baudrate = 64000;		/* XXX */
	IFQ_SET_MAXLEN(&ifp->if_snd, ifqmaxlen);
	ifp->if_snd.ifq_drv_maxlen = ifqmaxlen;
	IFQ_SET_READY(&ifp->if_snd);

	/* Give this node the same name as the interface (if possible) */
	if (ng_name_node(node, ifp->if_xname) != 0)
		log(LOG_WARNING, "%s: can't acquire netgraph name\n",
		    ifp->if_xname);

	/* Attach the interface */
	if_attach(ifp);
	bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));

	/* Done */
	return (0);
}

/*
 * Give our ok for a hook to be added