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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 websocket
import (
"errors"
"io"
"net"
"net/url"
"os"
"strconv"
"strings"
"sync"
)
type proxy_direct struct{}
// Direct is a direct proxy: one that makes network connections directly.
var proxy_Direct = proxy_direct{}
func (proxy_direct) Dial(network, addr string) (net.Conn, error) {
return net.Dial(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)
}
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.
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.
func proxy_FromEnvironment() proxy_Dialer {
allProxy := proxy_allProxyEnv.Get()
if len(allProxy) == 0 {
return proxy_Direct
}
proxyURL, err := url.Parse(allProxy)
if err != nil {
return proxy_Direct
}
proxy, err := proxy_FromURL(proxyURL, proxy_Direct)
if err != nil {
return proxy_Direct
}
noProxy := proxy_noProxyEnv.Get()
if len(noProxy) == 0 {
return proxy
}
perHost := proxy_NewPerHost(proxy, proxy_Direct)
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":
return proxy_SOCKS5("tcp", u.Host, 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
}
}
}
// 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, addr string, auth *proxy_Auth, forward proxy_Dialer) (proxy_Dialer, error) {
s := &proxy_socks5{
network: network,
addr: addr,
forward: forward,
}
if auth != nil {
s.user = auth.User
s.password = auth.Password
}
return s, nil
}
type proxy_socks5 struct {
user, password string
network, addr string
forward proxy_Dialer
}
const proxy_socks5Version = 5
const (
proxy_socks5AuthNone = 0
proxy_socks5AuthPassword = 2
)
const proxy_socks5Connect = 1
const (
proxy_socks5IP4 = 1
proxy_socks5Domain = 3
proxy_socks5IP6 = 4
)
var proxy_socks5Errors = []string{
"",
"general failure",
"connection forbidden",
"network unreachable",
"host unreachable",
"connection refused",
"TTL expired",
"command not supported",
"address type not supported",
}
// Dial connects to the address addr on the given network via the SOCKS5 proxy.
func (s *proxy_socks5) Dial(network, addr string) (net.Conn, error) {
switch network {
case "tcp", "tcp6", "tcp4":
default:
return nil, errors.New("proxy: no support for SOCKS5 proxy connections of type " + network)
}
conn, err := s.forward.Dial(s.network, s.addr)
if err != nil {
return nil, err
}
if err := s.connect(conn, addr); err != nil {
conn.Close()
return nil, err
}
return conn, nil
}
// connect takes an existing connection to a socks5 proxy server,
// and commands the server to extend that connection to target,
// which must be a canonical address with a host and port.
func (s *proxy_socks5) connect(conn net.Conn, target string) error {
host, portStr, err := net.SplitHostPort(target)
if err != nil {
return err
}
port, err := strconv.Atoi(portStr)
if err != nil {
return errors.New("proxy: failed to parse port number: " + portStr)
}
if port < 1 || port > 0xffff {
return errors.New("proxy: port number out of range: " + portStr)
}
// the size here is just an estimate
buf := make([]byte, 0, 6+len(host))
buf = append(buf, proxy_socks5Version)
if len(s.user) > 0 && len(s.user) < 256 && len(s.password) < 256 {
buf = append(buf, 2 /* num auth methods */, proxy_socks5AuthNone, proxy_socks5AuthPassword)
} else {
buf = append(buf, 1 /* num auth methods */, proxy_socks5AuthNone)
}
if _, err := conn.Write(buf); err != nil {
return errors.New("proxy: failed to write greeting to SOCKS5 proxy at " + s.addr + ": " + err.Error())
}
if _, err := io.ReadFull(conn, buf[:2]); err != nil {
return errors.New("proxy: failed to read greeting from SOCKS5 proxy at " + s.addr + ": " + err.Error())
}
if buf[0] != 5 {
return errors.New("proxy: SOCKS5 proxy at " + s.addr + " has unexpected version " + strconv.Itoa(int(buf[0])))
}
if buf[1] == 0xff {
return errors.New("proxy: SOCKS5 proxy at " + s.addr + " requires authentication")
}
// See RFC 1929
if buf[1] == proxy_socks5AuthPassword {
buf = buf[:0]
buf = append(buf, 1 /* password protocol version */)
buf = append(buf, uint8(len(s.user)))
buf = append(buf, s.user...)
buf = append(buf, uint8(len(s.password)))
buf = append(buf, s.password...)
if _, err := conn.Write(buf); err != nil {
return errors.New("proxy: failed to write authentication request to SOCKS5 proxy at " + s.addr + ": " + err.Error())
}
if _, err := io.ReadFull(conn, buf[:2]); err != nil {
return errors.New("proxy: failed to read authentication reply from SOCKS5 proxy at " + s.addr + ": " + err.Error())
}
if buf[1] != 0 {
return errors.New("proxy: SOCKS5 proxy at " + s.addr + " rejected username/password")
}
}
buf = buf[:0]
buf = append(buf, proxy_socks5Version, proxy_socks5Connect, 0 /* reserved */)
if ip := net.ParseIP(host); ip != nil {
if ip4 := ip.To4(); ip4 != nil {
buf = append(buf, proxy_socks5IP4)
ip = ip4
} else {
buf = append(buf, proxy_socks5IP6)
}
buf = append(buf, ip...)
} else {
if len(host) > 255 {
return errors.New("proxy: destination host name too long: " + host)
}
buf = append(buf, proxy_socks5Domain)
buf = append(buf, byte(len(host)))
buf = append(buf, host...)
}
buf = append(buf, byte(port>>8), byte(port))
if _, err := conn.Write(buf); err != nil {
return errors.New("proxy: failed to write connect request to SOCKS5 proxy at " + s.addr + ": " + err.Error())
}
if _, err := io.ReadFull(conn, buf[:4]); err != nil {
return errors.New("proxy: failed to read connect reply from SOCKS5 proxy at " + s.addr + ": " + err.Error())
}
failure := "unknown error"
if int(buf[1]) < len(proxy_socks5Errors) {
failure = proxy_socks5Errors[buf[1]]
}
if len(failure) > 0 {
return errors.New("proxy: SOCKS5 proxy at " + s.addr + " failed to connect: " + failure)
}
bytesToDiscard := 0
switch buf[3] {
case proxy_socks5IP4:
bytesToDiscard = net.IPv4len
case proxy_socks5IP6:
bytesToDiscard = net.IPv6len
case proxy_socks5Domain:
_, err := io.ReadFull(conn, buf[:1])
if err != nil {
return errors.New("proxy: failed to read domain length from SOCKS5 proxy at " + s.addr + ": " + err.Error())
}
bytesToDiscard = int(buf[0])
default:
return errors.New("proxy: got unknown address type " + strconv.Itoa(int(buf[3])) + " from SOCKS5 proxy at " + s.addr)
}
if cap(buf) < bytesToDiscard {
buf = make([]byte, bytesToDiscard)
} else {
buf = buf[:bytesToDiscard]
}
if _, err := io.ReadFull(conn, buf); err != nil {
return errors.New("proxy: failed to read address from SOCKS5 proxy at " + s.addr + ": " + err.Error())
}
// Also need to discard the port number
if _, err := io.ReadFull(conn, buf[:2]); err != nil {
return errors.New("proxy: failed to read port from SOCKS5 proxy at " + s.addr + ": " + err.Error())
}
return nil
}
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