1// Copyright 2015 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	"internal/testenv"
9	"os"
10	"runtime"
11	"strings"
12	"testing"
13)
14
15// testableNetwork reports whether network is testable on the current
16// platform configuration.
17func testableNetwork(network string) bool {
18	ss := strings.Split(network, ":")
19	switch ss[0] {
20	case "ip+nopriv":
21		switch runtime.GOOS {
22		case "nacl":
23			return false
24		}
25	case "ip", "ip4", "ip6":
26		switch runtime.GOOS {
27		case "nacl", "plan9":
28			return false
29		default:
30			if os.Getuid() != 0 {
31				return false
32			}
33		}
34	case "unix", "unixgram":
35		switch runtime.GOOS {
36		case "android", "nacl", "plan9", "windows":
37			return false
38		}
39		// iOS does not support unix, unixgram.
40		if runtime.GOOS == "darwin" && (runtime.GOARCH == "arm" || runtime.GOARCH == "arm64") {
41			return false
42		}
43	case "unixpacket":
44		switch runtime.GOOS {
45		case "android", "darwin", "nacl", "plan9", "windows":
46			fallthrough
47		case "freebsd": // FreeBSD 8 and below don't support unixpacket
48			return false
49		}
50	}
51	switch ss[0] {
52	case "tcp4", "udp4", "ip4":
53		if !supportsIPv4() {
54			return false
55		}
56	case "tcp6", "udp6", "ip6":
57		if !supportsIPv6() {
58			return false
59		}
60	}
61	return true
62}
63
64// testableAddress reports whether address of network is testable on
65// the current platform configuration.
66func testableAddress(network, address string) bool {
67	switch ss := strings.Split(network, ":"); ss[0] {
68	case "unix", "unixgram", "unixpacket":
69		// Abstract unix domain sockets, a Linux-ism.
70		if address[0] == '@' && runtime.GOOS != "linux" {
71			return false
72		}
73	}
74	return true
75}
76
77// testableListenArgs reports whether arguments are testable on the
78// current platform configuration.
79func testableListenArgs(network, address, client string) bool {
80	if !testableNetwork(network) || !testableAddress(network, address) {
81		return false
82	}
83
84	var err error
85	var addr Addr
86	switch ss := strings.Split(network, ":"); ss[0] {
87	case "tcp", "tcp4", "tcp6":
88		addr, err = ResolveTCPAddr("tcp", address)
89	case "udp", "udp4", "udp6":
90		addr, err = ResolveUDPAddr("udp", address)
91	case "ip", "ip4", "ip6":
92		addr, err = ResolveIPAddr("ip", address)
93	default:
94		return true
95	}
96	if err != nil {
97		return false
98	}
99	var ip IP
100	var wildcard bool
101	switch addr := addr.(type) {
102	case *TCPAddr:
103		ip = addr.IP
104		wildcard = addr.isWildcard()
105	case *UDPAddr:
106		ip = addr.IP
107		wildcard = addr.isWildcard()
108	case *IPAddr:
109		ip = addr.IP
110		wildcard = addr.isWildcard()
111	}
112
113	// Test wildcard IP addresses.
114	if wildcard && !testenv.HasExternalNetwork() {
115		return false
116	}
117
118	// Test functionality of IPv4 communication using AF_INET and
119	// IPv6 communication using AF_INET6 sockets.
120	if !supportsIPv4() && ip.To4() != nil {
121		return false
122	}
123	if !supportsIPv6() && ip.To16() != nil && ip.To4() == nil {
124		return false
125	}
126	cip := ParseIP(client)
127	if cip != nil {
128		if !supportsIPv4() && cip.To4() != nil {
129			return false
130		}
131		if !supportsIPv6() && cip.To16() != nil && cip.To4() == nil {
132			return false
133		}
134	}
135
136	// Test functionality of IPv4 communication using AF_INET6
137	// sockets.
138	if !supportsIPv4map() && supportsIPv4() && (network == "tcp" || network == "udp" || network == "ip") && wildcard {
139		// At this point, we prefer IPv4 when ip is nil.
140		// See favoriteAddrFamily for further information.
141		if ip.To16() != nil && ip.To4() == nil && cip.To4() != nil { // a pair of IPv6 server and IPv4 client
142			return false
143		}
144		if (ip.To4() != nil || ip == nil) && cip.To16() != nil && cip.To4() == nil { // a pair of IPv4 server and IPv6 client
145			return false
146		}
147	}
148
149	return true
150}
151
152var condFatalf = func() func(*testing.T, string, ...interface{}) {
153	// A few APIs, File, Read/WriteMsg{UDP,IP}, are not
154	// implemented yet on both Plan 9 and Windows.
155	switch runtime.GOOS {
156	case "plan9", "windows":
157		return (*testing.T).Logf
158	}
159	return (*testing.T).Fatalf
160}()
161