source: code/trunk/vendor/golang.org/x/net/proxy/socks5.go@ 145

// Copyright 2011 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 proxy

import (
        "context"
        "net"

        "golang.org/x/net/internal/socks"
)

// 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 SOCKS5(network, address string, auth *Auth, forward Dialer) (Dialer, error) {
        d := socks.NewDialer(network, address)
        if forward != nil {
                if f, ok := forward.(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 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
}