func lookupIface() (*net.Interface, net.IP, error) {
var iface *net.Interface
var ipaddr net.IP
var err error
if len(opts.iface) > 0 {
if ipaddr = net.ParseIP(opts.iface); ipaddr != nil {
iface, err = ip.GetInterfaceByIP(ipaddr)
if err != nil {
return nil, nil, fmt.Errorf("Error looking up interface %s: %s", opts.iface, err)
}
} else {
iface, err = net.InterfaceByName(opts.iface)
if err != nil {
return nil, nil, fmt.Errorf("Error looking up interface %s: %s", opts.iface, err)
}
}
} else {
log.Info("Determining IP address of default interface")
if iface, err = ip.GetDefaultGatewayIface(); err != nil {
return nil, nil, fmt.Errorf("Failed to get default interface: %s", err)
}
}
if ipaddr == nil {
ipaddr, err = ip.GetIfaceIP4Addr(iface)
if err != nil {
return nil, nil, fmt.Errorf("Failed to find IPv4 address for interface %s", iface.Name)
}
}
return iface, ipaddr, nil
}
func lookupExtIface(ifname string) (*backend.ExternalInterface, error) {
var iface *net.Interface
var iaddr net.IP
var err error
if len(ifname) > 0 {
if iaddr = net.ParseIP(ifname); iaddr != nil {
iface, err = ip.GetInterfaceByIP(iaddr)
if err != nil {
return nil, fmt.Errorf("error looking up interface %s: %s", ifname, err)
}
} else {
iface, err = net.InterfaceByName(ifname)
if err != nil {
return nil, fmt.Errorf("error looking up interface %s: %s", ifname, err)
}
}
} else {
log.Info("Determining IP address of default interface")
if iface, err = ip.GetDefaultGatewayIface(); err != nil {
return nil, fmt.Errorf("failed to get default interface: %s", err)
}
}
if iaddr == nil {
iaddr, err = ip.GetIfaceIP4Addr(iface)
if err != nil {
return nil, fmt.Errorf("failed to find IPv4 address for interface %s", iface.Name)
}
}
if iface.MTU == 0 {
return nil, fmt.Errorf("failed to determine MTU for %s interface", iaddr)
}
var eaddr net.IP
if len(opts.publicIP) > 0 {
eaddr = net.ParseIP(opts.publicIP)
if eaddr == nil {
return nil, fmt.Errorf("invalid public IP address", opts.publicIP)
}
}
if eaddr == nil {
eaddr = iaddr
}
log.Infof("Using %s as external interface", iaddr)
log.Infof("Using %s as external endpoint", eaddr)
return &backend.ExternalInterface{
Iface: iface,
IfaceAddr: iaddr,
ExtAddr: eaddr,
}, nil
}