// Copyright 2011 The Go Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. //go:build darwin || dragonfly || freebsd || netbsd || openbsd package net import ( "os" "runtime" "syscall" ) func setDefaultSockopts(s, family, sotype int, ipv6only bool) error { if runtime.GOOS == "dragonfly" && sotype != syscall.SOCK_RAW { // On DragonFly BSD, we adjust the ephemeral port // range because unlike other BSD systems its default // port range doesn't conform to IANA recommendation // as described in RFC 6056 and is pretty narrow. switch family { case syscall.AF_INET: syscall.SetsockoptInt(s, syscall.IPPROTO_IP, syscall.IP_PORTRANGE, syscall.IP_PORTRANGE_HIGH) case syscall.AF_INET6: syscall.SetsockoptInt(s, syscall.IPPROTO_IPV6, syscall.IPV6_PORTRANGE, syscall.IPV6_PORTRANGE_HIGH) } } if family == syscall.AF_INET6 && sotype != syscall.SOCK_RAW && supportsIPv4map() { // Allow both IP versions even if the OS default // is otherwise. Note that some operating systems // never admit this option. syscall.SetsockoptInt(s, syscall.IPPROTO_IPV6, syscall.IPV6_V6ONLY, boolint(ipv6only)) } if (sotype == syscall.SOCK_DGRAM || sotype == syscall.SOCK_RAW) && family != syscall.AF_UNIX { // Allow broadcast. return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_BROADCAST, 1)) } return nil } func setDefaultListenerSockopts(s int) error { // Allow reuse of recently-used addresses. return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1)) } func setDefaultMulticastSockopts(s int) error { // Allow multicast UDP and raw IP datagram sockets to listen // concurrently across multiple listeners. if err := syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1); err != nil { return os.NewSyscallError("setsockopt", err) } // Allow reuse of recently-used ports. // This option is supported only in descendants of 4.4BSD, // to make an effective multicast application that requires // quick draw possible. return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEPORT, 1)) }