// Copyright 2014 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. // Package nettest provides utilities for network testing. package nettest // import "golang.org/x/net/internal/nettest" import ( "fmt" "io/ioutil" "net" "os" "runtime" ) var ( supportsIPv4 bool supportsIPv6 bool ) func init() { if ln, err := net.Listen("tcp4", "127.0.0.1:0"); err == nil { ln.Close() supportsIPv4 = true } if ln, err := net.Listen("tcp6", "[::1]:0"); err == nil { ln.Close() supportsIPv6 = true } } // SupportsIPv4 reports whether the platform supports IPv4 networking // functionality. func SupportsIPv4() bool { return supportsIPv4 } // SupportsIPv6 reports whether the platform supports IPv6 networking // functionality. func SupportsIPv6() bool { return supportsIPv6 } // SupportsRawIPSocket reports whether the platform supports raw IP // sockets. func SupportsRawIPSocket() (string, bool) { return supportsRawIPSocket() } // SupportsIPv6MulticastDeliveryOnLoopback reports whether the // platform supports IPv6 multicast packet delivery on software // loopback interface. func SupportsIPv6MulticastDeliveryOnLoopback() bool { return supportsIPv6MulticastDeliveryOnLoopback() } // ProtocolNotSupported reports whether err is a protocol not // supported error. func ProtocolNotSupported(err error) bool { return protocolNotSupported(err) } // TestableNetwork reports whether network is testable on the current // platform configuration. func TestableNetwork(network string) bool { // This is based on logic from standard library's // net/platform_test.go. switch network { case "unix", "unixgram": switch runtime.GOOS { case "android", "js", "nacl", "plan9", "windows": return false } if runtime.GOOS == "darwin" && (runtime.GOARCH == "arm" || runtime.GOARCH == "arm64") { return false } case "unixpacket": switch runtime.GOOS { case "android", "darwin", "freebsd", "js", "nacl", "plan9", "windows": return false case "netbsd": // It passes on amd64 at least. 386 fails (Issue 22927). arm is unknown. if runtime.GOARCH == "386" { return false } } } return true } // NewLocalListener returns a listener which listens to a loopback IP // address or local file system path. // Network must be "tcp", "tcp4", "tcp6", "unix" or "unixpacket". func NewLocalListener(network string) (net.Listener, error) { switch network { case "tcp": if supportsIPv4 { if ln, err := net.Listen("tcp4", "127.0.0.1:0"); err == nil { return ln, nil } } if supportsIPv6 { return net.Listen("tcp6", "[::1]:0") } case "tcp4": if supportsIPv4 { return net.Listen("tcp4", "127.0.0.1:0") } case "tcp6": if supportsIPv6 { return net.Listen("tcp6", "[::1]:0") } case "unix", "unixpacket": return net.Listen(network, localPath()) } return nil, fmt.Errorf("%s is not supported", network) } // NewLocalPacketListener returns a packet listener which listens to a // loopback IP address or local file system path. // Network must be "udp", "udp4", "udp6" or "unixgram". func NewLocalPacketListener(network string) (net.PacketConn, error) { switch network { case "udp": if supportsIPv4 { if c, err := net.ListenPacket("udp4", "127.0.0.1:0"); err == nil { return c, nil } } if supportsIPv6 { return net.ListenPacket("udp6", "[::1]:0") } case "udp4": if supportsIPv4 { return net.ListenPacket("udp4", "127.0.0.1:0") } case "udp6": if supportsIPv6 { return net.ListenPacket("udp6", "[::1]:0") } case "unixgram": return net.ListenPacket(network, localPath()) } return nil, fmt.Errorf("%s is not supported", network) } func localPath() string { f, err := ioutil.TempFile("", "nettest") if err != nil { panic(err) } path := f.Name() f.Close() os.Remove(path) return path }