package dialer import ( "net" "syscall" "golang.org/x/sys/unix" ) func setSocketOptions(network, address string, c syscall.RawConn, opts *Options) (err error) { if opts == nil || !isTCPSocket(network) && !isUDPSocket(network) { return } var innerErr error err = c.Control(func(fd uintptr) { host, _, _ := net.SplitHostPort(address) if ip := net.ParseIP(host); ip != nil && !ip.IsGlobalUnicast() { return } if opts.InterfaceName == "" && opts.InterfaceIndex != 0 { if iface, err := net.InterfaceByIndex(opts.InterfaceIndex); err == nil { opts.InterfaceName = iface.Name } } if opts.InterfaceName != "" { if innerErr = unix.BindToDevice(int(fd), opts.InterfaceName); innerErr != nil { return } } if opts.RoutingMark != 0 { if innerErr = unix.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_MARK, opts.RoutingMark); innerErr != nil { return } } }) if innerErr != nil { err = innerErr } return }