Function vxlan_setup_multicast

freebsd/net/if_vxlan.c:1473–1508

}

static int
vxlan_setup_multicast(struct vxlan_softc *sc)
{
	const union vxlan_sockaddr *group;
	int error;

	group = &sc->vxl_dst_addr;
	error = 0;

	if (sc->vxl_mc_ifname[0] != '\0') {
		error = vxlan_setup_multicast_interface(sc);
		if (error)
			return (error);
	}

	/*
	 * Initialize an multicast options structure that is sufficiently
	 * populated for use in the respective IP output routine. This
	 * structure is typically stored in the socket, but our sockets
	 * may be shared among multiple interfaces.
	 */
	if (VXLAN_SOCKADDR_IS_IPV4(group)) {
		sc->vxl_im4o = malloc(sizeof(struct ip_moptions), M_VXLAN,
		    M_ZERO | M_WAITOK);
		sc->vxl_im4o->imo_multicast_ifp = sc->vxl_mc_ifp;
		sc->vxl_im4o->imo_multicast_ttl = sc->vxl_ttl;
		sc->vxl_im4o->imo_multicast_vif = -1;
	} else if (VXLAN_SOCKADDR_IS_IPV6(group)) {
		sc->vxl_im6o = malloc(sizeof(struct ip6_moptions), M_VXLAN,
		    M_ZERO | M_WAITOK);
		sc->vxl_im6o->im6o_multicast_ifp = sc->vxl_mc_ifp;
		sc->vxl_im6o->im6o_multicast_hlim = sc->vxl_ttl;
	}

	return (error);
}

static int
vxlan_setup_socket(struct vxlan_softc *sc)