proxy.php

<?php

/**
 * @name PHP Proxy
 * @author Jens Segers
 * @link http://www.jenssegers.be
 * @license MIT License Copyright (c) 2013 Jens Segers
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
class Proxy {
 
 // curl handle
 protected $ch;
 
 // configuration
 protected $config = array();

 /**
 * New proxy instance
 */
 function __construct()
 {
 // load the config
 $config = array();
 require "config.php";
 
 // check config
 if (!count($config)) die("Please provide a valid configuration");
 
 $this->config = $config;
 
 // initialize curl
 $this->ch = curl_init();
 @curl_setopt($this->ch, CURLOPT_FOLLOWLOCATION, true);
 curl_setopt($this->ch, CURLOPT_MAXREDIRS, 10);
 curl_setopt($this->ch, CURLOPT_RETURNTRANSFER, true);
 curl_setopt($this->ch, CURLOPT_SSL_VERIFYPEER, false);
 curl_setopt($this->ch, CURLOPT_SSL_VERIFYHOST, false);
 curl_setopt($this->ch, CURLOPT_HEADER, true);
 curl_setopt($this->ch, CURLOPT_TIMEOUT, $this->config["timeout"]);
 curl_setopt($this->ch, CURLOPT_USERAGENT, "PHP Proxy"); 
 if (!empty($this->config['user']) && !empty($this->config['pass'])){
 curl_setopt($this->ch, CURLOPT_USERPWD, "{$this->config['user']}:{$this->config['pass']}");
 curl_setopt($this->ch, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 }
 }
 
 /**
 * Forward the current request to this url
 *
 * @param string $url
 */
 public function forward($url = '')
 {
 // build the correct url
 if (isset($_SERVER["HTTPS"]) && $_SERVER["HTTPS"] == "on")
 {
 $url = "https://" . $this->config["server"] . ":" . $this->config["https_port"] . "/" . ltrim($url, "/");
 } 
 else 
 {
 $url = "http://" . $this->config["server"] . ":" . $this->config["http_port"] . "/" . ltrim($url, "/");
 }
 
 // set url
 curl_setopt($this->ch, CURLOPT_URL, $url);
 
 // forward request headers
 $headers = $this->get_request_headers();
 $this->set_request_headers($headers);
 
 // forward post
 if ($_SERVER["REQUEST_METHOD"] == "POST")
 {
 if(in_array($this->get_content_type($headers), array('application/x-www-form-urlencoded','multipart/form-data')))
 {
 $this->set_post($_POST);
 }
 else
 {
 // just grab the raw post data
 $fp = fopen('php://input','r');
 $post = stream_get_contents($fp);
 fclose($fp);
 $this->set_post($post);
 }
 
 } elseif ($_SERVER["REQUEST_METHOD"] == "HEAD") {
 curl_setopt($this->ch, CURLOPT_NOBODY, true);
 }
 
 // execute
 $data = curl_exec($this->ch);
 $info = curl_getinfo($this->ch);
 
 // extract response from headers
 $body = $info["size_download"] ? substr($data, $info["header_size"], $info["size_download"]) : "";
 
 // forward response headers
 $headers = substr($data, 0, $info["header_size"]);
 $this->set_response_headers($headers);
 
 // close connection
 curl_close($this->ch);
 
 // output html
 echo $body;
 }
 
 /**
 * Get the content-type of the request
 */
 protected function get_content_type( $headers )
 {
 foreach( $headers as $name => $value ){
 if( 'content-type' == strtolower($name) ){
 $parts = explode(';', $value);
 return strtolower($parts[0]);
 }
 }
 return null;
 }
 
 /**
 * Get the headers of the current request
 */
 protected function get_request_headers()
 {
 // use native getallheaders function
 if (function_exists('getallheaders')) return getallheaders();

 // fallback
 $headers = '';
 foreach ($_SERVER as $name => $value)
 {
 if (substr($name, 0, 5) == 'HTTP_')
 {
 $headers[str_replace(' ', '-', ucwords(strtolower(str_replace('_', ' ', substr($name, 5)))))] = $value;
 }
 }

 return $headers;
 }

 /**
 * Pass the request headers to cURL
 *
 * @param array $request
 */
 protected function set_request_headers($request)
 {
 // headers to strip
 $strip = array("Content-Length", "Host");
 
 $headers = array();
 foreach ($request as $key => $value)
 {
 if ($key && !in_array($key, $strip))
 {
 $headers[] = "$key: $value";
 }
 }
 
 curl_setopt($this->ch, CURLOPT_HTTPHEADER, $headers);
 }
 
 /**
 * Pass the cURL response headers to the user
 *
 * @param array $response
 */
 protected function set_response_headers($response)
 {
 // headers to strip
 $strip = array("Transfer-Encoding");
 
 // split headers into an array
 $headers = explode("\n", $response);
 
 // process response headers
 foreach ($headers as &$header)
 {
 // skip empty headers
 if (!$header) continue;
 
 // get header key
 $pos = strpos($header, ":");
 $key = substr($header, 0, $pos);
 
 // modify redirects
 if (strtolower($key) == "location")
 {
 $base_url = $_SERVER["HTTP_HOST"];
 $base_url .= rtrim(str_replace(basename($_SERVER["SCRIPT_NAME"]), "", $_SERVER["SCRIPT_NAME"]), "/");
 
 // replace ports and forward url
 $header = str_replace(":" . $this->config["http_port"], "", $header);
 $header = str_replace(":" . $this->config["https_port"], "", $header);
 $header = str_replace($this->config["server"], $base_url, $header);
 }
 
 // set headers
 if (!in_array($key, $strip))
 {
 header($header, FALSE);
 }
 }
 }
 
 /**
 * Set POST values including FILES support
 *
 * @param array $post
 */
 protected function set_post($post)
 {
 // file upload support
 if (count($_FILES))
 {
 foreach ($_FILES as $key => $file)
 {
 $parts = pathinfo($file["tmp_name"]);
 $name = $parts["dirname"] . "/" . $file["name"];
 rename($file["tmp_name"], $name);
 $post[$key] = "@" . $name;
 }
 } 
 else if( is_array( $post ) )
 {
 $post = http_build_query($post);
 }
 
 curl_setopt($this->ch, CURLOPT_POST, 1);
 curl_setopt($this->ch, CURLOPT_POSTFIELDS, $post);
 }

}