libgo/go/net/sockopt_bsd.go

   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
   5 //go:build darwin || dragonfly || freebsd || netbsd || openbsd
   6
   7 package net
   8
   9 import (
  10         "os"
  11         "runtime"
  12         "syscall"
  13 )
  14
  15 func setDefaultSockopts(s, family, sotype int, ipv6only bool) error {
  16         if runtime.GOOS == "dragonfly" && sotype != syscall.SOCK_RAW {
  17                 // On DragonFly BSD, we adjust the ephemeral port
  18                 // range because unlike other BSD systems its default
  19                 // port range doesn't conform to IANA recommendation
  20                 // as described in RFC 6056 and is pretty narrow.
  21                 switch family {
  22                 case syscall.AF_INET:
  23                         syscall.SetsockoptInt(s, syscall.IPPROTO_IP, syscall.IP_PORTRANGE, syscall.IP_PORTRANGE_HIGH)
  24                 case syscall.AF_INET6:
  25                         syscall.SetsockoptInt(s, syscall.IPPROTO_IPV6, syscall.IPV6_PORTRANGE, syscall.IPV6_PORTRANGE_HIGH)
  26                 }
  27         }
  28         if family == syscall.AF_INET6 && sotype != syscall.SOCK_RAW && supportsIPv4map() {
  29                 // Allow both IP versions even if the OS default
  30                 // is otherwise. Note that some operating systems
  31                 // never admit this option.
  32                 syscall.SetsockoptInt(s, syscall.IPPROTO_IPV6, syscall.IPV6_V6ONLY, boolint(ipv6only))
  33         }
  34         if (sotype == syscall.SOCK_DGRAM || sotype == syscall.SOCK_RAW) && family != syscall.AF_UNIX {
  35                 // Allow broadcast.
  36                 return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_BROADCAST, 1))
  37         }
  38         return nil
  39 }
  40
  41 func setDefaultListenerSockopts(s int) error {
  42         // Allow reuse of recently-used addresses.
  43         return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1))
  44 }
  45
  46 func setDefaultMulticastSockopts(s int) error {
  47         // Allow multicast UDP and raw IP datagram sockets to listen
  48         // concurrently across multiple listeners.
  49         if err := syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1); err != nil {
  50                 return os.NewSyscallError("setsockopt", err)
  51         }
  52         // Allow reuse of recently-used ports.
  53         // This option is supported only in descendants of 4.4BSD,
  54         // to make an effective multicast application that requires
  55         // quick draw possible.
  56         if syscall.SO_REUSEPORT != 0 {
  57                 return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEPORT, 1))
  58         }
  59         return nil
  60 }