ngx_http_proxy_connect_module

This module provides support for the "CONNECT" HTTP method.
This method is mainly used to tunnel SSL requests through proxy servers.

Example

 server {
     listen                         3128;

     # dns resolver used by forward proxying
     resolver                       8.8.8.8;

     # forward proxy for CONNECT request
     proxy_connect;
     proxy_connect_allow            443 563;
     proxy_connect_connect_timeout  10s;
     proxy_connect_read_timeout     10s;
     proxy_connect_send_timeout     10s;

     # forward proxy for non-CONNECT request
     location / {
         proxy_pass http://$host;
         proxy_set_header Host $host;
     }
 }

With above configuration, you can get any https website via HTTP CONNECT tunnel. A simple test with command curl is as following:

$ curl https://github.com/ -v -x 127.0.0.1:3128
*   Trying 127.0.0.1...
* Connected to 127.0.0.1 (127.0.0.1) port 3128 (#0)
* Establish HTTP proxy tunnel to github.com:443
> CONNECT github.com:443 HTTP/1.1
> Host: github.com:443
> User-Agent: curl/7.43.0
> Proxy-Connection: Keep-Alive
>
< HTTP/1.0 200 Connection Established
< Proxy-agent: nginx
<
* Proxy replied OK to CONNECT request
* TLS 1.2 connection using TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
* Server certificate: github.com
* Server certificate: DigiCert SHA2 Extended Validation Server CA
* Server certificate: DigiCert High Assurance EV Root CA
> GET / HTTP/1.1
> Host: github.com
> User-Agent: curl/7.43.0
> Accept: */*
>
< HTTP/1.1 200 OK
< Date: Fri, 11 Aug 2017 04:13:57 GMT
< Content-Type: text/html; charset=utf-8
< Transfer-Encoding: chunked
< Server: GitHub.com
< Status: 200 OK
< Cache-Control: no-cache
< Vary: X-PJAX
...
... <other response headers & response body> ...
...

Also you can configure your browser to use this nginx as PROXY server.

Directive

proxy_connect

Syntax: proxy_connect
Default: none
Context: server

Enable "CONNECT" HTTP method support.

proxy_connect_allow

Syntax: proxy_connect_allow all | [port ...] | [port-range ...]
Default: 443 563
Context: server

This directive specifies a list of port numbers or ranges to which the proxy CONNECT method may connect.
By default, only the default https port (443) and the default snews port (563) are enabled.
Using this directive will override this default and allow connections to the listed ports only.

The value all will allow all ports to proxy.

The value port will allow specified port to proxy.

The value port-range will allow specified range of port to proxy, for example:

proxy_connect_allow 1000-2000 3000-4000; # allow range of port from 1000 to 2000, from 3000 to 4000.

proxy_connect_connect_timeout

Syntax: proxy_connect_connect_timeout time
Default: none
Context: server

Defines a timeout for establishing a connection with a proxied server.

proxy_connect_read_timeout

Syntax: proxy_connect_read_timeout time
Default: 60s
Context: server

Defines a timeout for reading a response from the proxied server.
The timeout is set only between two successive read operations, not for the transmission of the whole response.
If the proxied server does not transmit anything within this time, the connection is closed.

proxy_connect_write_timeout

Syntax: proxy_connect_write_timeout time Default: 60s Context: server

Sets a timeout for transmitting a request to the proxied server.
The timeout is set only between two successive write operations, not for the transmission of the whole request.
If the proxied server does not receive anything within this time, the connection is closed.

Variables

$connect_host

host name from CONNECT request line.

$connect_port

port from CONNECT request line.

$connect_addr

IP address and port of the remote host, e.g. "192.168.1.5:12345". IP address is resolved from host name of CONNECT request line.

Nginx Compatibility

The latest module is compatible with the following versions of nginx:

• 1.12.1 (stable version of 1.12.x)
• 1.10.3 (stable version of 1.10.x)
• 1.8.1 (stable version of 1.8.x)
• 1.6.3 (stable version of 1.6.x)
• 1.4.7 (stable version of 1.4.x)

Tengine Compatibility

This module will be merged into tengine soon, see this pull request.

Install

Install this module from source:

$ wget http://nginx.org/download/nginx-1.9.2.tar.gz
$ tar -xzvf nginx-1.9.2.tar.gz
$ cd nginx-1.9.2/
$ patch -p1 < /path/to/ngx_http_proxy_connect_module/proxy_connect.patch
$ ./configure --add-module=/path/to/ngx_http_proxy_connect_module
$ make && make install

Note that proxy_connect.patch includes logic in macro NGX_HTTP_RPOXY_CONNECT, and config script will enable this macro automatically.

Author

This module was developed by Peng Qi originally.
He contributed this module to Tengine in this pull request.

I build this module for Nginx proper based on his pull request.