为什么curl 似乎不能在代理后面工作？

Question

当在代理后面使用curl时，

curl -O -fsSL https://storage.googleapis.com/tensorflow-serving-apt/tensorflow-serving.release.pub.gpg -v -k -x http://xxx.xxx.xxx.xxx:8080

我有一个错误，如下所示。我能做什么来解决这个问题？

Trying xxx.xxx.xxx.xxx...
TCP_NODELAY set
Connected to xxx.xxx.xxx.xxx (xxx.xxx.xxx.xxx) port 8080 (#0)
Establish HTTP proxy tunnel to storage.googleapis.com:443
CONNECT storage.googleapis.com:443 HTTP/1.1
Host: storage.googleapis.com:443
User-Agent: curl/7.54.0
Proxy-Connection: Keep-Alive

HTTP/1.0 403 Forbidden
Server: squid
Mime-Version: 1.0
Date: Sun, 13 Jan 2019 16:33:30 GMT
Content-Type: text/html
Content-Length: 3149
X-Squid-Error: ERR_ACCESS_DENIED 0
Vary: Accept-Language
Content-Language: en
X-Cache: MISS from unknown
X-Cache-Lookup: NONE from unknown:8080
Via: 1.0 unknown (squid)
Connection: keep-alive

The requested URL returned error: 403
Connection #0 to host xxx.xxx.xxx.xxx left intact
curl: (22) The requested URL returned error: 403

---

我尝试过一些其他的事情...

1. 没有代理，它可以工作...

   curl -O -fsSL https://storage.googleapis.com/tensorflow-serving-apt/tensorflow-serving.release.pub.gpg -v -k
   

2. 当使用如下代理访问一个特定 URL 时，它会起作用......

   curl -O -fsSL https://get.docker.com/gpg -v -k -x http://xxx.xxx.xxx.xxx:8080
   
   SSL connection using TLSv1.2 / ECDHE-RSA-AES128-GCM-SHA256
   ALPN, server accepted to use http/1.1
   Server certificate:
    subject: CN=*.docker.com
    start date: Jul 30 00:00:00 2018 GMT
    expire date: Aug 30 12:00:00 2019 GMT
    issuer: C=US; O=Amazon; OU=Server CA 1B; CN=Amazon
    SSL certificate verify ok.
   GET /gpg HTTP/1.0
   Host: get.docker.com
   User-Agent: curl/7.54.0
   Accept: */*
   
   HTTP/1.1 200 OK
   Content-Type: binary/octet-stream
   Content-Length: 975
   Connection: close
   Date: Thu, 03 Jan 2019 02:11:40 GMT
   Last-Modified: Tue, 16 Oct 2018 22:59:33 GMT
   x-amz-version-id: JhVckjyzQEkrDSsxn3RySEOXcybUYG7B
   ETag: "5be321089b71e829affab91dd5d5cd3f"
   Server: AmazonS3
   Age: 856
   X-Cache: Hit from cloudfront
   Via: 1.1 a8f6d439d4b35a734e48cf0ced363c2d.cloudfront.net (CloudFront)
   X-Amz-Cf-Id: 07fsnwsaA-9G6q5peUxScboc7l1y5Bov_t5vys0Fp6msPMt9oaXQ2w==
   

3. 当使用代理访问其他 URL 时，会返回相同的错误。

   curl -O -fsSL https://www.google.com/images/branding/googlelogo/1x/googlelogo_color_272x92dp.png -v -k -x http://xxx.xxx.xxx.xxx:8080
   Connection #0 to host 10.132.2.6 left intact
   curl: (22) The requested URL returned error: 403
   

4. -v4添加了、-v6、--http1.0、 或 等选项--http2.0，但没有解决问题。