通过具有基本身份验证的HTTP代理访问HTTPS

Question

I am trying to make a GET request against an HTTPS URL using proxy with username/password authorization (auth is required by the proxy not the website). Here's what I do:

package main

import (
    "crypto/tls"
    "encoding/base64"
    "fmt"
    "net/http"
    "net/http/httputil"
    "net/url"
)

func main() {
    ua := "Mozilla/5.0 (Windows NT 6.1"
    basic := "Basic " + base64.StdEncoding.EncodeToString([]byte("username:mypass"))
    req, err := http.NewRequest("GET", "https://api.ipify.org/", nil)
    proxyUrl, _ := url.Parse("http://myproxy.com:9999")
    fmt.Println(basic) // Basic dXNlcm5hbWU6bXlwYXNz
    req.Header.Add("Proxy-Authorization", basic)
    req.Header.Add("User-Agent", ua)
    bb, _ := httputil.DumpRequest(req, false)
    fmt.Println(string(bb))
    /*
    Get / HTTP/1.1
    Host: api.ipify.org
    Proxy-Authorization: Basic dXNlcm5hbWU6bXlwYXNz
    User-Agent: Mozilla/5.0 (Windows NT 6.1
    */
    client := &http.Client{
        Transport: &http.Transport{
            TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
            Proxy:           http.ProxyURL(proxyUrl),
        },
    }
    resp, err := client.Do(req)
    fmt.Println(err)  // Proxy Authentication Required
    fmt.Println(resp) // <nil>
}

The catch is that when I try to do a request to an HTTP (not HTTPS) site it goes fine, but if I make HTTPS request it fails (see above the message).

I tested the proxy with my browser (FireFox) and everything goes well, I looked for the headers through firebug and added everything relevant to the request (above). I've double-triple-checked the basic value and everything else but without any luck.

So does some one have any idea why this happens or at least how do I research the problem?

The last thing to add is that I can use a public HTTP proxy (that doesn't require any auth) in this case and problems seem to start when auth enters in this process (the error also suggests that).

P.S. Unfortunately I cannot share the proxy IP, port and username cause it is against their policy.

Answer 1

package main

import (
    "crypto/tls"
    "fmt"
    "net/url"
    "net/http"
)

func main() {
    req, err := http.NewRequest("GET", "https://api.ipify.org/", nil)
    proxyUrl, _ := url.Parse("http://username:password@127.0.0.1:9999")
    client := &http.Client{
        Transport: &http.Transport{
            TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
            Proxy:           http.ProxyURL(proxyUrl),
        },
    }
    _, err = client.Do(req)
    fmt.Println(err)
}