/
x_net_proxy.go
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/
x_net_proxy.go
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// Code generated by golang.org/x/tools/cmd/bundle. DO NOT EDIT.
//go:generate bundle -o x_net_proxy.go golang.org/x/net/proxy
// Package proxy provides support for a variety of protocols to proxy network
// data.
//
package proxy
import (
"context"
"errors"
"net"
"net/url"
"os"
"strings"
"sync"
)
// A ContextDialer dials using a context.
type proxy_ContextDialer interface {
DialContext(ctx context.Context, network, address string) (net.Conn, error)
}
// Dial works like DialContext on net.Dialer but using a dialer returned by FromEnvironment.
//
// The passed ctx is only used for returning the Conn, not the lifetime of the Conn.
//
// Custom dialers (registered via RegisterDialerType) that do not implement ContextDialer
// can leak a goroutine for as long as it takes the underlying Dialer implementation to timeout.
//
// A Conn returned from a successful Dial after the context has been cancelled will be immediately closed.
func proxy_Dial(ctx context.Context, network, address string) (net.Conn, error) {
d := proxy_FromEnvironment()
if xd, ok := d.(proxy_ContextDialer); ok {
return xd.DialContext(ctx, network, address)
}
return proxy_dialContext(ctx, d, network, address)
}
// WARNING: this can leak a goroutine for as long as the underlying Dialer implementation takes to timeout
// A Conn returned from a successful Dial after the context has been cancelled will be immediately closed.
func proxy_dialContext(ctx context.Context, d proxy_Dialer, network, address string) (net.Conn, error) {
var (
conn net.Conn
done = make(chan struct{}, 1)
err error
)
go func() {
conn, err = d.Dial(network, address)
close(done)
if conn != nil && ctx.Err() != nil {
conn.Close()
}
}()
select {
case <-ctx.Done():
err = ctx.Err()
case <-done:
}
return conn, err
}
type proxy_direct struct{}
// Direct implements Dialer by making network connections directly using net.Dial or net.DialContext.
var proxy_Direct = proxy_direct{}
var (
_ proxy_Dialer = proxy_Direct
_ proxy_ContextDialer = proxy_Direct
)
// Dial directly invokes net.Dial with the supplied parameters.
func (proxy_direct) Dial(network, addr string) (net.Conn, error) {
return net.Dial(network, addr)
}
// DialContext instantiates a net.Dialer and invokes its DialContext receiver with the supplied parameters.
func (proxy_direct) DialContext(ctx context.Context, network, addr string) (net.Conn, error) {
var d net.Dialer
return d.DialContext(ctx, network, addr)
}
// A PerHost directs connections to a default Dialer unless the host name
// requested matches one of a number of exceptions.
type proxy_PerHost struct {
def, bypass proxy_Dialer
bypassNetworks []*net.IPNet
bypassIPs []net.IP
bypassZones []string
bypassHosts []string
}
// NewPerHost returns a PerHost Dialer that directs connections to either
// defaultDialer or bypass, depending on whether the connection matches one of
// the configured rules.
func proxy_NewPerHost(defaultDialer, bypass proxy_Dialer) *proxy_PerHost {
return &proxy_PerHost{
def: defaultDialer,
bypass: bypass,
}
}
// Dial connects to the address addr on the given network through either
// defaultDialer or bypass.
func (p *proxy_PerHost) Dial(network, addr string) (c net.Conn, err error) {
host, _, err := net.SplitHostPort(addr)
if err != nil {
return nil, err
}
return p.dialerForRequest(host).Dial(network, addr)
}
// DialContext connects to the address addr on the given network through either
// defaultDialer or bypass.
func (p *proxy_PerHost) DialContext(ctx context.Context, network, addr string) (c net.Conn, err error) {
host, _, err := net.SplitHostPort(addr)
if err != nil {
return nil, err
}
d := p.dialerForRequest(host)
if x, ok := d.(proxy_ContextDialer); ok {
return x.DialContext(ctx, network, addr)
}
return proxy_dialContext(ctx, d, network, addr)
}
func (p *proxy_PerHost) dialerForRequest(host string) proxy_Dialer {
if ip := net.ParseIP(host); ip != nil {
for _, net := range p.bypassNetworks {
if net.Contains(ip) {
return p.bypass
}
}
for _, bypassIP := range p.bypassIPs {
if bypassIP.Equal(ip) {
return p.bypass
}
}
return p.def
}
for _, zone := range p.bypassZones {
if strings.HasSuffix(host, zone) {
return p.bypass
}
if host == zone[1:] {
// For a zone ".example.com", we match "example.com"
// too.
return p.bypass
}
}
for _, bypassHost := range p.bypassHosts {
if bypassHost == host {
return p.bypass
}
}
return p.def
}
// AddFromString parses a string that contains comma-separated values
// specifying hosts that should use the bypass proxy. Each value is either an
// IP address, a CIDR range, a zone (*.example.com) or a host name
// (localhost). A best effort is made to parse the string and errors are
// ignored.
func (p *proxy_PerHost) AddFromString(s string) {
hosts := strings.Split(s, ",")
for _, host := range hosts {
host = strings.TrimSpace(host)
if len(host) == 0 {
continue
}
if strings.Contains(host, "/") {
// We assume that it's a CIDR address like 127.0.0.0/8
if _, net, err := net.ParseCIDR(host); err == nil {
p.AddNetwork(net)
}
continue
}
if ip := net.ParseIP(host); ip != nil {
p.AddIP(ip)
continue
}
if strings.HasPrefix(host, "*.") {
p.AddZone(host[1:])
continue
}
p.AddHost(host)
}
}
// AddIP specifies an IP address that will use the bypass proxy. Note that
// this will only take effect if a literal IP address is dialed. A connection
// to a named host will never match an IP.
func (p *proxy_PerHost) AddIP(ip net.IP) {
p.bypassIPs = append(p.bypassIPs, ip)
}
// AddNetwork specifies an IP range that will use the bypass proxy. Note that
// this will only take effect if a literal IP address is dialed. A connection
// to a named host will never match.
func (p *proxy_PerHost) AddNetwork(net *net.IPNet) {
p.bypassNetworks = append(p.bypassNetworks, net)
}
// AddZone specifies a DNS suffix that will use the bypass proxy. A zone of
// "example.com" matches "example.com" and all of its subdomains.
func (p *proxy_PerHost) AddZone(zone string) {
if strings.HasSuffix(zone, ".") {
zone = zone[:len(zone)-1]
}
if !strings.HasPrefix(zone, ".") {
zone = "." + zone
}
p.bypassZones = append(p.bypassZones, zone)
}
// AddHost specifies a host name that will use the bypass proxy.
func (p *proxy_PerHost) AddHost(host string) {
if strings.HasSuffix(host, ".") {
host = host[:len(host)-1]
}
p.bypassHosts = append(p.bypassHosts, host)
}
// A Dialer is a means to establish a connection.
// Custom dialers should also implement ContextDialer.
type proxy_Dialer interface {
// Dial connects to the given address via the proxy.
Dial(network, addr string) (c net.Conn, err error)
}
// Auth contains authentication parameters that specific Dialers may require.
type proxy_Auth struct {
User, Password string
}
// FromEnvironment returns the dialer specified by the proxy-related
// variables in the environment and makes underlying connections
// directly.
func proxy_FromEnvironment() proxy_Dialer {
return proxy_FromEnvironmentUsing(proxy_Direct)
}
// FromEnvironmentUsing returns the dialer specify by the proxy-related
// variables in the environment and makes underlying connections
// using the provided forwarding Dialer (for instance, a *net.Dialer
// with desired configuration).
func proxy_FromEnvironmentUsing(forward proxy_Dialer) proxy_Dialer {
allProxy := proxy_allProxyEnv.Get()
if len(allProxy) == 0 {
return forward
}
proxyURL, err := url.Parse(allProxy)
if err != nil {
return forward
}
proxy, err := proxy_FromURL(proxyURL, forward)
if err != nil {
return forward
}
noProxy := proxy_noProxyEnv.Get()
if len(noProxy) == 0 {
return proxy
}
perHost := proxy_NewPerHost(proxy, forward)
perHost.AddFromString(noProxy)
return perHost
}
// proxySchemes is a map from URL schemes to a function that creates a Dialer
// from a URL with such a scheme.
var proxy_proxySchemes map[string]func(*url.URL, proxy_Dialer) (proxy_Dialer, error)
// RegisterDialerType takes a URL scheme and a function to generate Dialers from
// a URL with that scheme and a forwarding Dialer. Registered schemes are used
// by FromURL.
func proxy_RegisterDialerType(scheme string, f func(*url.URL, proxy_Dialer) (proxy_Dialer, error)) {
if proxy_proxySchemes == nil {
proxy_proxySchemes = make(map[string]func(*url.URL, proxy_Dialer) (proxy_Dialer, error))
}
proxy_proxySchemes[scheme] = f
}
// FromURL returns a Dialer given a URL specification and an underlying
// Dialer for it to make network requests.
func proxy_FromURL(u *url.URL, forward proxy_Dialer) (proxy_Dialer, error) {
var auth *proxy_Auth
if u.User != nil {
auth = new(proxy_Auth)
auth.User = u.User.Username()
if p, ok := u.User.Password(); ok {
auth.Password = p
}
}
switch u.Scheme {
case "socks5", "socks5h":
addr := u.Hostname()
port := u.Port()
if port == "" {
port = "1080"
}
return proxy_SOCKS5("tcp", net.JoinHostPort(addr, port), auth, forward)
}
// If the scheme doesn't match any of the built-in schemes, see if it
// was registered by another package.
if proxy_proxySchemes != nil {
if f, ok := proxy_proxySchemes[u.Scheme]; ok {
return f(u, forward)
}
}
return nil, errors.New("proxy: unknown scheme: " + u.Scheme)
}
var (
proxy_allProxyEnv = &proxy_envOnce{
names: []string{"ALL_PROXY", "all_proxy"},
}
proxy_noProxyEnv = &proxy_envOnce{
names: []string{"NO_PROXY", "no_proxy"},
}
)
// envOnce looks up an environment variable (optionally by multiple
// names) once. It mitigates expensive lookups on some platforms
// (e.g. Windows).
// (Borrowed from net/http/transport.go)
type proxy_envOnce struct {
names []string
once sync.Once
val string
}
func (e *proxy_envOnce) Get() string {
e.once.Do(e.init)
return e.val
}
func (e *proxy_envOnce) init() {
for _, n := range e.names {
e.val = os.Getenv(n)
if e.val != "" {
return
}
}
}
// reset is used by tests
func (e *proxy_envOnce) reset() {
e.once = sync.Once{}
e.val = ""
}
// SOCKS5 returns a Dialer that makes SOCKSv5 connections to the given
// address with an optional username and password.
// See RFC 1928 and RFC 1929.
func proxy_SOCKS5(network, address string, auth *proxy_Auth, forward proxy_Dialer) (proxy_Dialer, error) {
d := socks_NewDialer(network, address)
if forward != nil {
if f, ok := forward.(proxy_ContextDialer); ok {
d.ProxyDial = func(ctx context.Context, network string, address string) (net.Conn, error) {
return f.DialContext(ctx, network, address)
}
} else {
d.ProxyDial = func(ctx context.Context, network string, address string) (net.Conn, error) {
return proxy_dialContext(ctx, forward, network, address)
}
}
}
if auth != nil {
up := socks_UsernamePassword{
Username: auth.User,
Password: auth.Password,
}
d.AuthMethods = []socks_AuthMethod{
socks_AuthMethodNotRequired,
socks_AuthMethodUsernamePassword,
}
d.Authenticate = up.Authenticate
}
return d, nil
}