package sockopt import ( "syscall" "golang.org/x/sys/unix" ) func control(opt *Options) func(network, address string, c syscall.RawConn) error { return func(network, address string, c syscall.RawConn) (err error) { return c.Control(func(fd uintptr) { if opt.bindIface != nil { switch network { case "tcp4", "udp4": unix.SetsockoptInt(int(fd), unix.IPPROTO_IP, unix.IP_BOUND_IF, opt.bindIface.Index) case "tcp6", "udp6": unix.SetsockoptInt(int(fd), unix.IPPROTO_IPV6, unix.IPV6_BOUND_IF, opt.bindIface.Index) } } if opt.reuseAddr { unix.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_REUSEADDR, 1) unix.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_REUSEPORT, 1) } }) } }