1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
|
// Copyright 2009 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.
// IP sockets
package net
import (
"os"
)
var supportsIPv6, supportsIPv4map = probeIPv6Stack()
func firstFavoriteAddr(filter func(IP) IP, addrs []string) (addr IP) {
if filter == anyaddr {
// We'll take any IP address, but since the dialing code
// does not yet try multiple addresses, prefer to use
// an IPv4 address if possible. This is especially relevant
// if localhost resolves to [ipv6-localhost, ipv4-localhost].
// Too much code assumes localhost == ipv4-localhost.
addr = firstSupportedAddr(ipv4only, addrs)
if addr == nil {
addr = firstSupportedAddr(anyaddr, addrs)
}
} else {
addr = firstSupportedAddr(filter, addrs)
}
return
}
func firstSupportedAddr(filter func(IP) IP, addrs []string) IP {
for _, s := range addrs {
if addr := filter(ParseIP(s)); addr != nil {
return addr
}
}
return nil
}
func anyaddr(x IP) IP {
if x4 := x.To4(); x4 != nil {
return x4
}
if supportsIPv6 {
return x
}
return nil
}
func ipv4only(x IP) IP { return x.To4() }
func ipv6only(x IP) IP {
// Only return addresses that we can use
// with the kernel's IPv6 addressing modes.
if len(x) == IPv6len && x.To4() == nil && supportsIPv6 {
return x
}
return nil
}
type InvalidAddrError string
func (e InvalidAddrError) String() string { return string(e) }
func (e InvalidAddrError) Timeout() bool { return false }
func (e InvalidAddrError) Temporary() bool { return false }
// SplitHostPort splits a network address of the form
// "host:port" or "[host]:port" into host and port.
// The latter form must be used when host contains a colon.
func SplitHostPort(hostport string) (host, port string, err os.Error) {
// The port starts after the last colon.
i := last(hostport, ':')
if i < 0 {
err = &AddrError{"missing port in address", hostport}
return
}
host, port = hostport[0:i], hostport[i+1:]
// Can put brackets around host ...
if len(host) > 0 && host[0] == '[' && host[len(host)-1] == ']' {
host = host[1 : len(host)-1]
} else {
// ... but if there are no brackets, no colons.
if byteIndex(host, ':') >= 0 {
err = &AddrError{"too many colons in address", hostport}
return
}
}
return
}
// JoinHostPort combines host and port into a network address
// of the form "host:port" or, if host contains a colon, "[host]:port".
func JoinHostPort(host, port string) string {
// If host has colons, have to bracket it.
if byteIndex(host, ':') >= 0 {
return "[" + host + "]:" + port
}
return host + ":" + port
}
// Convert "host:port" into IP address and port.
func hostPortToIP(net, hostport string) (ip IP, iport int, err os.Error) {
var (
addr IP
p, i int
ok bool
)
host, port, err := SplitHostPort(hostport)
if err != nil {
goto Error
}
if host != "" {
// Try as an IP address.
addr = ParseIP(host)
if addr == nil {
filter := anyaddr
if net != "" && net[len(net)-1] == '4' {
filter = ipv4only
}
if net != "" && net[len(net)-1] == '6' {
filter = ipv6only
}
// Not an IP address. Try as a DNS name.
addrs, err1 := LookupHost(host)
if err1 != nil {
err = err1
goto Error
}
addr = firstFavoriteAddr(filter, addrs)
if addr == nil {
// should not happen
err = &AddrError{"LookupHost returned no suitable address", addrs[0]}
goto Error
}
}
}
p, i, ok = dtoi(port, 0)
if !ok || i != len(port) {
p, err = LookupPort(net, port)
if err != nil {
goto Error
}
}
if p < 0 || p > 0xFFFF {
err = &AddrError{"invalid port", port}
goto Error
}
return addr, p, nil
Error:
return nil, 0, err
}
|
