1// Copyright 2011 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5package net
6
7import (
8	"os"
9	"syscall"
10)
11
12func setDefaultSockopts(s, family, sotype int, ipv6only bool) error {
13	if family == syscall.AF_INET6 && sotype != syscall.SOCK_RAW {
14		// Allow both IP versions even if the OS default
15		// is otherwise. Note that some operating systems
16		// never admit this option.
17		syscall.SetsockoptInt(s, syscall.IPPROTO_IPV6, syscall.IPV6_V6ONLY, boolint(ipv6only))
18	}
19	if (sotype == syscall.SOCK_DGRAM || sotype == syscall.SOCK_RAW) && family != syscall.AF_UNIX {
20		// Allow broadcast.
21		return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_BROADCAST, 1))
22	}
23	return nil
24}
25
26func setDefaultListenerSockopts(s int) error {
27	// Allow reuse of recently-used addresses.
28	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1))
29}
30
31func setDefaultMulticastSockopts(s int) error {
32	// Allow multicast UDP and raw IP datagram sockets to listen
33	// concurrently across multiple listeners.
34	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1))
35}
36