diff --git a/html/inc/ReCaptcha/ReCaptcha.php b/html/inc/ReCaptcha/ReCaptcha.php
new file mode 100644
index 0000000000..7139fae37b
--- /dev/null
+++ b/html/inc/ReCaptcha/ReCaptcha.php
@@ -0,0 +1,97 @@
+<?php
+/**
+ * This is a PHP library that handles calling reCAPTCHA.
+ *
+ * @copyright Copyright (c) 2015, Google Inc.
+ * @link      http://www.google.com/recaptcha
+ *
+ * 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.
+ */
+
+namespace ReCaptcha;
+
+/**
+ * reCAPTCHA client.
+ */
+class ReCaptcha
+{
+    /**
+     * Version of this client library.
+     * @const string
+     */
+    const VERSION = 'php_1.1.2';
+
+    /**
+     * Shared secret for the site.
+     * @var type string
+     */
+    private $secret;
+
+    /**
+     * Method used to communicate with service. Defaults to POST request.
+     * @var RequestMethod
+     */
+    private $requestMethod;
+
+    /**
+     * Create a configured instance to use the reCAPTCHA service.
+     *
+     * @param string $secret shared secret between site and reCAPTCHA server.
+     * @param RequestMethod $requestMethod method used to send the request. Defaults to POST.
+     */
+    public function __construct($secret, RequestMethod $requestMethod = null)
+    {
+        if (empty($secret)) {
+            throw new \RuntimeException('No secret provided');
+        }
+
+        if (!is_string($secret)) {
+            throw new \RuntimeException('The provided secret must be a string');
+        }
+
+        $this->secret = $secret;
+
+        if (!is_null($requestMethod)) {
+            $this->requestMethod = $requestMethod;
+        } else {
+            $this->requestMethod = new RequestMethod\Post();
+        }
+    }
+
+    /**
+     * Calls the reCAPTCHA siteverify API to verify whether the user passes
+     * CAPTCHA test.
+     *
+     * @param string $response The value of 'g-recaptcha-response' in the submitted form.
+     * @param string $remoteIp The end user's IP address.
+     * @return Response Response from the service.
+     */
+    public function verify($response, $remoteIp = null)
+    {
+        // Discard empty solution submissions
+        if (empty($response)) {
+            $recaptchaResponse = new Response(false, array('missing-input-response'));
+            return $recaptchaResponse;
+        }
+
+        $params = new RequestParameters($this->secret, $response, $remoteIp, self::VERSION);
+        $rawResponse = $this->requestMethod->submit($params);
+        return Response::fromJson($rawResponse);
+    }
+}
diff --git a/html/inc/ReCaptcha/RequestMethod.php b/html/inc/ReCaptcha/RequestMethod.php
new file mode 100644
index 0000000000..fc4dde59c0
--- /dev/null
+++ b/html/inc/ReCaptcha/RequestMethod.php
@@ -0,0 +1,42 @@
+<?php
+/**
+ * This is a PHP library that handles calling reCAPTCHA.
+ *
+ * @copyright Copyright (c) 2015, Google Inc.
+ * @link      http://www.google.com/recaptcha
+ *
+ * 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.
+ */
+
+namespace ReCaptcha;
+
+/**
+ * Method used to send the request to the service.
+ */
+interface RequestMethod
+{
+
+    /**
+     * Submit the request with the specified parameters.
+     *
+     * @param RequestParameters $params Request parameters
+     * @return string Body of the reCAPTCHA response
+     */
+    public function submit(RequestParameters $params);
+}
diff --git a/html/inc/ReCaptcha/RequestMethod/Curl.php b/html/inc/ReCaptcha/RequestMethod/Curl.php
new file mode 100644
index 0000000000..20ee53099c
--- /dev/null
+++ b/html/inc/ReCaptcha/RequestMethod/Curl.php
@@ -0,0 +1,74 @@
+<?php
+/**
+ * This is a PHP library that handles calling reCAPTCHA.
+ *
+ * @copyright Copyright (c) 2015, Google Inc.
+ * @link      http://www.google.com/recaptcha
+ *
+ * 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.
+ */
+
+namespace ReCaptcha\RequestMethod;
+
+/**
+ * Convenience wrapper around the cURL functions to allow mocking.
+ */
+class Curl
+{
+
+    /**
+     * @see http://php.net/curl_init
+     * @param string $url
+     * @return resource cURL handle
+     */
+    public function init($url = null)
+    {
+        return curl_init($url);
+    }
+
+    /**
+     * @see http://php.net/curl_setopt_array
+     * @param resource $ch
+     * @param array $options
+     * @return bool
+     */
+    public function setoptArray($ch, array $options)
+    {
+        return curl_setopt_array($ch, $options);
+    }
+
+    /**
+     * @see http://php.net/curl_exec
+     * @param resource $ch
+     * @return mixed
+     */
+    public function exec($ch)
+    {
+        return curl_exec($ch);
+    }
+
+    /**
+     * @see http://php.net/curl_close
+     * @param resource $ch
+     */
+    public function close($ch)
+    {
+        curl_close($ch);
+    }
+}
diff --git a/html/inc/ReCaptcha/RequestMethod/CurlPost.php b/html/inc/ReCaptcha/RequestMethod/CurlPost.php
new file mode 100644
index 0000000000..e06d1cc8fe
--- /dev/null
+++ b/html/inc/ReCaptcha/RequestMethod/CurlPost.php
@@ -0,0 +1,88 @@
+<?php
+/**
+ * This is a PHP library that handles calling reCAPTCHA.
+ *
+ * @copyright Copyright (c) 2015, Google Inc.
+ * @link      http://www.google.com/recaptcha
+ *
+ * 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.
+ */
+
+namespace ReCaptcha\RequestMethod;
+
+use ReCaptcha\RequestMethod;
+use ReCaptcha\RequestParameters;
+
+/**
+ * Sends cURL request to the reCAPTCHA service.
+ * Note: this requires the cURL extension to be enabled in PHP
+ * @see http://php.net/manual/en/book.curl.php
+ */
+class CurlPost implements RequestMethod
+{
+    /**
+     * URL to which requests are sent via cURL.
+     * @const string
+     */
+    const SITE_VERIFY_URL = 'https://www.google.com/recaptcha/api/siteverify';
+
+    /**
+     * Curl connection to the reCAPTCHA service
+     * @var Curl
+     */
+    private $curl;
+
+    public function __construct(Curl $curl = null)
+    {
+        if (!is_null($curl)) {
+            $this->curl = $curl;
+        } else {
+            $this->curl = new Curl();
+        }
+    }
+
+    /**
+     * Submit the cURL request with the specified parameters.
+     *
+     * @param RequestParameters $params Request parameters
+     * @return string Body of the reCAPTCHA response
+     */
+    public function submit(RequestParameters $params)
+    {
+        $handle = $this->curl->init(self::SITE_VERIFY_URL);
+
+        $options = array(
+            CURLOPT_POST => true,
+            CURLOPT_POSTFIELDS => $params->toQueryString(),
+            CURLOPT_HTTPHEADER => array(
+                'Content-Type: application/x-www-form-urlencoded'
+            ),
+            CURLINFO_HEADER_OUT => false,
+            CURLOPT_HEADER => false,
+            CURLOPT_RETURNTRANSFER => true,
+            CURLOPT_SSL_VERIFYPEER => true
+        );
+        $this->curl->setoptArray($handle, $options);
+
+        $response = $this->curl->exec($handle);
+        $this->curl->close($handle);
+
+        return $response;
+    }
+}
diff --git a/html/inc/ReCaptcha/RequestMethod/Post.php b/html/inc/ReCaptcha/RequestMethod/Post.php
new file mode 100644
index 0000000000..7770d90814
--- /dev/null
+++ b/html/inc/ReCaptcha/RequestMethod/Post.php
@@ -0,0 +1,70 @@
+<?php
+/**
+ * This is a PHP library that handles calling reCAPTCHA.
+ *
+ * @copyright Copyright (c) 2015, Google Inc.
+ * @link      http://www.google.com/recaptcha
+ *
+ * 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.
+ */
+
+namespace ReCaptcha\RequestMethod;
+
+use ReCaptcha\RequestMethod;
+use ReCaptcha\RequestParameters;
+
+/**
+ * Sends POST requests to the reCAPTCHA service.
+ */
+class Post implements RequestMethod
+{
+    /**
+     * URL to which requests are POSTed.
+     * @const string
+     */
+    const SITE_VERIFY_URL = 'https://www.google.com/recaptcha/api/siteverify';
+
+    /**
+     * Submit the POST request with the specified parameters.
+     *
+     * @param RequestParameters $params Request parameters
+     * @return string Body of the reCAPTCHA response
+     */
+    public function submit(RequestParameters $params)
+    {
+        /**
+         * PHP 5.6.0 changed the way you specify the peer name for SSL context options.
+         * Using "CN_name" will still work, but it will raise deprecated errors.
+         */
+        $peer_key = version_compare(PHP_VERSION, '5.6.0', '<') ? 'CN_name' : 'peer_name';
+        $options = array(
+            'http' => array(
+                'header' => "Content-type: application/x-www-form-urlencoded\r\n",
+                'method' => 'POST',
+                'content' => $params->toQueryString(),
+                // Force the peer to validate (not needed in 5.6.0+, but still works
+                'verify_peer' => true,
+                // Force the peer validation to use www.google.com
+                $peer_key => 'www.google.com',
+            ),
+        );
+        $context = stream_context_create($options);
+        return file_get_contents(self::SITE_VERIFY_URL, false, $context);
+    }
+}
diff --git a/html/inc/ReCaptcha/RequestMethod/Socket.php b/html/inc/ReCaptcha/RequestMethod/Socket.php
new file mode 100644
index 0000000000..f51f1239a9
--- /dev/null
+++ b/html/inc/ReCaptcha/RequestMethod/Socket.php
@@ -0,0 +1,104 @@
+<?php
+/**
+ * This is a PHP library that handles calling reCAPTCHA.
+ *
+ * @copyright Copyright (c) 2015, Google Inc.
+ * @link      http://www.google.com/recaptcha
+ *
+ * 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.
+ */
+
+namespace ReCaptcha\RequestMethod;
+
+/**
+ * Convenience wrapper around native socket and file functions to allow for
+ * mocking.
+ */
+class Socket
+{
+    private $handle = null;
+
+    /**
+     * fsockopen
+     * 
+     * @see http://php.net/fsockopen
+     * @param string $hostname
+     * @param int $port
+     * @param int $errno
+     * @param string $errstr
+     * @param float $timeout
+     * @return resource
+     */
+    public function fsockopen($hostname, $port = -1, &$errno = 0, &$errstr = '', $timeout = null)
+    {
+        $this->handle = fsockopen($hostname, $port, $errno, $errstr, (is_null($timeout) ? ini_get("default_socket_timeout") : $timeout));
+
+        if ($this->handle != false && $errno === 0 && $errstr === '') {
+            return $this->handle;
+        }
+        return false;
+    }
+
+    /**
+     * fwrite
+     * 
+     * @see http://php.net/fwrite
+     * @param string $string
+     * @param int $length
+     * @return int | bool
+     */
+    public function fwrite($string, $length = null)
+    {
+        return fwrite($this->handle, $string, (is_null($length) ? strlen($string) : $length));
+    }
+
+    /**
+     * fgets
+     * 
+     * @see http://php.net/fgets
+     * @param int $length
+     * @return string
+     */
+    public function fgets($length = null)
+    {
+        return fgets($this->handle, $length);
+    }
+
+    /**
+     * feof
+     * 
+     * @see http://php.net/feof
+     * @return bool
+     */
+    public function feof()
+    {
+        return feof($this->handle);
+    }
+
+    /**
+     * fclose
+     * 
+     * @see http://php.net/fclose
+     * @return bool
+     */
+    public function fclose()
+    {
+        return fclose($this->handle);
+    }
+}
diff --git a/html/inc/ReCaptcha/RequestMethod/SocketPost.php b/html/inc/ReCaptcha/RequestMethod/SocketPost.php
new file mode 100644
index 0000000000..47541215f0
--- /dev/null
+++ b/html/inc/ReCaptcha/RequestMethod/SocketPost.php
@@ -0,0 +1,121 @@
+<?php
+/**
+ * This is a PHP library that handles calling reCAPTCHA.
+ *
+ * @copyright Copyright (c) 2015, Google Inc.
+ * @link      http://www.google.com/recaptcha
+ *
+ * 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.
+ */
+
+namespace ReCaptcha\RequestMethod;
+
+use ReCaptcha\RequestMethod;
+use ReCaptcha\RequestParameters;
+
+/**
+ * Sends a POST request to the reCAPTCHA service, but makes use of fsockopen()
+ * instead of get_file_contents(). This is to account for people who may be on
+ * servers where allow_furl_open is disabled.
+ */
+class SocketPost implements RequestMethod
+{
+    /**
+     * reCAPTCHA service host.
+     * @const string
+     */
+    const RECAPTCHA_HOST = 'www.google.com';
+
+    /**
+     * @const string reCAPTCHA service path
+     */
+    const SITE_VERIFY_PATH = '/recaptcha/api/siteverify';
+
+    /**
+     * @const string Bad request error
+     */
+    const BAD_REQUEST = '{"success": false, "error-codes": ["invalid-request"]}';
+
+    /**
+     * @const string Bad response error
+     */
+    const BAD_RESPONSE = '{"success": false, "error-codes": ["invalid-response"]}';
+
+    /**
+     * Socket to the reCAPTCHA service
+     * @var Socket
+     */
+    private $socket;
+
+    /**
+     * Constructor
+     *
+     * @param \ReCaptcha\RequestMethod\Socket $socket optional socket, injectable for testing
+     */
+    public function __construct(Socket $socket = null)
+    {
+        if (!is_null($socket)) {
+            $this->socket = $socket;
+        } else {
+            $this->socket = new Socket();
+        }
+    }
+
+    /**
+     * Submit the POST request with the specified parameters.
+     *
+     * @param RequestParameters $params Request parameters
+     * @return string Body of the reCAPTCHA response
+     */
+    public function submit(RequestParameters $params)
+    {
+        $errno = 0;
+        $errstr = '';
+
+        if (false === $this->socket->fsockopen('ssl://' . self::RECAPTCHA_HOST, 443, $errno, $errstr, 30)) {
+            return self::BAD_REQUEST;
+        }
+
+        $content = $params->toQueryString();
+
+        $request = "POST " . self::SITE_VERIFY_PATH . " HTTP/1.1\r\n";
+        $request .= "Host: " . self::RECAPTCHA_HOST . "\r\n";
+        $request .= "Content-Type: application/x-www-form-urlencoded\r\n";
+        $request .= "Content-length: " . strlen($content) . "\r\n";
+        $request .= "Connection: close\r\n\r\n";
+        $request .= $content . "\r\n\r\n";
+
+        $this->socket->fwrite($request);
+        $response = '';
+
+        while (!$this->socket->feof()) {
+            $response .= $this->socket->fgets(4096);
+        }
+
+        $this->socket->fclose();
+
+        if (0 !== strpos($response, 'HTTP/1.1 200 OK')) {
+            return self::BAD_RESPONSE;
+        }
+
+        $parts = preg_split("#\n\s*\n#Uis", $response);
+
+        return $parts[1];
+    }
+}
diff --git a/html/inc/ReCaptcha/RequestParameters.php b/html/inc/ReCaptcha/RequestParameters.php
new file mode 100644
index 0000000000..cb66f26cf4
--- /dev/null
+++ b/html/inc/ReCaptcha/RequestParameters.php
@@ -0,0 +1,103 @@
+<?php
+/**
+ * This is a PHP library that handles calling reCAPTCHA.
+ *
+ * @copyright Copyright (c) 2015, Google Inc.
+ * @link      http://www.google.com/recaptcha
+ *
+ * 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.
+ */
+
+namespace ReCaptcha;
+
+/**
+ * Stores and formats the parameters for the request to the reCAPTCHA service.
+ */
+class RequestParameters
+{
+    /**
+     * Site secret.
+     * @var string
+     */
+    private $secret;
+
+    /**
+     * Form response.
+     * @var string
+     */
+    private $response;
+
+    /**
+     * Remote user's IP address.
+     * @var string
+     */
+    private $remoteIp;
+
+    /**
+     * Client version.
+     * @var string
+     */
+    private $version;
+
+    /**
+     * Initialise parameters.
+     *
+     * @param string $secret Site secret.
+     * @param string $response Value from g-captcha-response form field.
+     * @param string $remoteIp User's IP address.
+     * @param string $version Version of this client library.
+     */
+    public function __construct($secret, $response, $remoteIp = null, $version = null)
+    {
+        $this->secret = $secret;
+        $this->response = $response;
+        $this->remoteIp = $remoteIp;
+        $this->version = $version;
+    }
+
+    /**
+     * Array representation.
+     *
+     * @return array Array formatted parameters.
+     */
+    public function toArray()
+    {
+        $params = array('secret' => $this->secret, 'response' => $this->response);
+
+        if (!is_null($this->remoteIp)) {
+            $params['remoteip'] = $this->remoteIp;
+        }
+
+        if (!is_null($this->version)) {
+            $params['version'] = $this->version;
+        }
+
+        return $params;
+    }
+
+    /**
+     * Query string representation for HTTP request.
+     *
+     * @return string Query string formatted parameters.
+     */
+    public function toQueryString()
+    {
+        return http_build_query($this->toArray(), '', '&');
+    }
+}
diff --git a/html/inc/ReCaptcha/Response.php b/html/inc/ReCaptcha/Response.php
new file mode 100644
index 0000000000..d2d8a8bf77
--- /dev/null
+++ b/html/inc/ReCaptcha/Response.php
@@ -0,0 +1,102 @@
+<?php
+/**
+ * This is a PHP library that handles calling reCAPTCHA.
+ *
+ * @copyright Copyright (c) 2015, Google Inc.
+ * @link      http://www.google.com/recaptcha
+ *
+ * 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.
+ */
+
+namespace ReCaptcha;
+
+/**
+ * The response returned from the service.
+ */
+class Response
+{
+    /**
+     * Succes or failure.
+     * @var boolean
+     */
+    private $success = false;
+
+    /**
+     * Error code strings.
+     * @var array
+     */
+    private $errorCodes = array();
+
+    /**
+     * Build the response from the expected JSON returned by the service.
+     *
+     * @param string $json
+     * @return \ReCaptcha\Response
+     */
+    public static function fromJson($json)
+    {
+        $responseData = json_decode($json, true);
+
+        if (!$responseData) {
+            return new Response(false, array('invalid-json'));
+        }
+
+        if (isset($responseData['success']) && $responseData['success'] == true) {
+            return new Response(true);
+        }
+
+        if (isset($responseData['error-codes']) && is_array($responseData['error-codes'])) {
+            return new Response(false, $responseData['error-codes']);
+        }
+
+        return new Response(false);
+    }
+
+    /**
+     * Constructor.
+     *
+     * @param boolean $success
+     * @param array $errorCodes
+     */
+    public function __construct($success, array $errorCodes = array())
+    {
+        $this->success = $success;
+        $this->errorCodes = $errorCodes;
+    }
+
+    /**
+     * Is success?
+     *
+     * @return boolean
+     */
+    public function isSuccess()
+    {
+        return $this->success;
+    }
+
+    /**
+     * Get error codes.
+     *
+     * @return array
+     */
+    public function getErrorCodes()
+    {
+        return $this->errorCodes;
+    }
+}
diff --git a/html/inc/profile.inc b/html/inc/profile.inc
index ee81a29ffa..dd083a7537 100644
--- a/html/inc/profile.inc
+++ b/html/inc/profile.inc
@@ -24,7 +24,6 @@ require_once("../inc/user.inc");
 require_once("../inc/translation.inc");
 require_once("../inc/text_transform.inc");
 require_once("../inc/forum.inc");
-require_once("../inc/recaptchalib.php");
 
 define('SMALL_IMG_WIDTH', 64);
 define('SMALL_IMG_HEIGHT', 64);
diff --git a/html/inc/recaptcha_loader.php b/html/inc/recaptcha_loader.php
new file mode 100644
index 0000000000..b7f475fdd7
--- /dev/null
+++ b/html/inc/recaptcha_loader.php
@@ -0,0 +1,42 @@
+<?php
+
+/* This is a copy of src/autoloader.php of the Google ReCaptcha implementation at
+ * https://github.com/google/recaptcha
+ */
+
+/* An autoloader for ReCaptcha\Foo classes. This should be require()d
+ * by the user before attempting to instantiate any of the ReCaptcha
+ * classes.
+ */
+
+spl_autoload_register(function ($class) {
+    if (substr($class, 0, 10) !== 'ReCaptcha\\') {
+      /* If the class does not lie under the "ReCaptcha" namespace,
+       * then we can exit immediately.
+       */
+      return;
+    }
+
+    /* All of the classes have names like "ReCaptcha\Foo", so we need
+     * to replace the backslashes with frontslashes if we want the
+     * name to map directly to a location in the filesystem.
+     */
+    $class = str_replace('\\', '/', $class);
+
+    /* First, check under the current directory. It is important that
+     * we look here first, so that we don't waste time searching for
+     * test classes in the common case.
+     */
+    $path = dirname(__FILE__).'/'.$class.'.php';
+    if (is_readable($path)) {
+        require_once $path;
+    }
+
+    /* If we didn't find what we're looking for already, maybe it's
+     * a test class?
+     */
+    $path = dirname(__FILE__).'/../tests/'.$class.'.php';
+    if (is_readable($path)) {
+        require_once $path;
+    }
+});
diff --git a/html/inc/recaptchalib.php b/html/inc/recaptchalib.php
index f8efafc432..6437fed987 100644
--- a/html/inc/recaptchalib.php
+++ b/html/inc/recaptchalib.php
@@ -1,140 +1,59 @@
 <?php
-/**
- * This is a PHP library that handles calling reCAPTCHA.
- *    - Documentation and latest version
- *          https://developers.google.com/recaptcha/docs/php
- *    - Get a reCAPTCHA API Key
- *          https://www.google.com/recaptcha/admin/create
- *    - Discussion group
- *          http://groups.google.com/group/recaptcha
- *
- * @copyright Copyright (c) 2014, Google Inc.
- * @link      http://www.google.com/recaptcha
- *
- * 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.
- */
+// This file is part of BOINC.
+// http://boinc.berkeley.edu
+// Copyright (C) 2015 University of California
+//
+// BOINC is free software; you can redistribute it and/or modify it
+// under the terms of the GNU Lesser General Public License
+// as published by the Free Software Foundation,
+// either version 3 of the License, or (at your option) any later version.
+//
+// BOINC is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with BOINC.  If not, see <http://www.gnu.org/licenses/>.
 
-/**
- * A ReCaptchaResponse is returned from checkAnswer().
- */
-class ReCaptchaResponse
-{
-    public $success;
-    public $errorCodes;
-}
+// recaptcha utilities
 
-class ReCaptcha
-{
-    private static $_signupUrl = "https://www.google.com/recaptcha/admin";
-    private static $_siteVerifyUrl =
-        "https://www.google.com/recaptcha/api/siteverify?";
-    private $_secret;
-    private static $_version = "php_1.0";
+// do not include the loader from somewhere else
+require('../inc/recaptcha_loader.php');
 
-    /**
-     * Constructor.
-     *
-     * @param string $secret shared secret between site and ReCAPTCHA server.
-     */
-    function ReCaptcha($secret)
-    {
-        if ($secret == null || $secret == "") {
-            die("To use reCAPTCHA you must get an API key from <a href='"
-                . self::$_signupUrl . "'>" . self::$_signupUrl . "</a>");
-        }
-        $this->_secret=$secret;
-    }
-
-    /**
-     * Encodes the given data into a query string format.
-     *
-     * @param array $data array of string elements to be encoded.
-     *
-     * @return string - encoded request.
-     */
-    private function _encodeQS($data)
-    {
-        $req = "";
-        foreach ($data as $key => $value) {
-            $req .= $key . '=' . urlencode(stripslashes($value)) . '&';
-        }
-
-        // Cut the last '&'
-        $req=substr($req, 0, strlen($req)-1);
-        return $req;
-    }
-
-    /**
-     * Submits an HTTP GET to a reCAPTCHA server.
-     *
-     * @param string $path url path to recaptcha server.
-     * @param array  $data array of parameters to be sent.
-     *
-     * @return array response
-     */
-    private function _submitHTTPGet($path, $data)
-    {
-        $req = $this->_encodeQS($data);
-        $response = file_get_contents($path . $req);
-        return $response;
-    }
-
-    /**
-     * Calls the reCAPTCHA siteverify API to verify whether the user passes
-     * CAPTCHA test.
-     *
-     * @param string $remoteIp   IP address of end user.
-     * @param string $response   response string from recaptcha verification.
-     *
-     * @return ReCaptchaResponse
-     */
-    public function verifyResponse($remoteIp, $response)
-    {
-        // Discard empty solution submissions
-        if ($response == null || strlen($response) == 0) {
-            $recaptchaResponse = new ReCaptchaResponse();
-            $recaptchaResponse->success = false;
-            $recaptchaResponse->errorCodes = 'missing-input';
-            return $recaptchaResponse;
-        }
-
-        $getResponse = $this->_submitHttpGet(
-            self::$_siteVerifyUrl,
-            array (
-                'secret' => $this->_secret,
-                'remoteip' => $remoteIp,
-                'v' => self::$_version,
-                'response' => $response
-            )
-        );
-        $answers = json_decode($getResponse, true);
-        $recaptchaResponse = new ReCaptchaResponse();
-
-        if (trim($answers ['success']) == true) {
-            $recaptchaResponse->success = true;
-        } else {
-            $recaptchaResponse->success = false;
-            $recaptchaResponse->errorCodes = $answers["error-codes"];
-        }
-
-        return $recaptchaResponse;
+function boinc_recaptcha_get_head_extra() {
+    // are we using recaptcha?
+    $publickey = parse_config(get_config(), "<recaptcha_public_key>");
+    if ($publickey) {
+        // the meta tag must be included
+        // for Recaptcha to work with some IE browsers
+        return '<meta http-equiv="X-UA-Compatible" content="IE=EmulateIE8" >
+        <script src="https://www.google.com/recaptcha/api.js" async defer></script>';
+    } else {
+        return null;
     }
 }
 
-?>
+function boinc_recaptcha_get_html($publickey) {
+    if ($publickey) {
+        return '<div class="g-recaptcha" data-sitekey="' . $publickey . '"></div>';
+    } else {
+        return '';
+    }
+}
+
+// wrapper for ReCaptcha implementation
+// returns true if the captcha was correct or no $privatekey was supplied
+// everything else means there was an error verifying the captcha
+//
+function boinc_recaptcha_isValidated($privatekey) {
+    if ($privatekey) {
+        // tells ReCaptcha to use fsockopen() instead of get_file_contents()
+        $recaptcha = new \ReCaptcha\ReCaptcha($privatekey, new \ReCaptcha\RequestMethod\SocketPost());
+        $resp = $recaptcha->verify($_POST['g-recaptcha-response'], $_SERVER['REMOTE_ADDR']);
+        return $resp->isSuccess();
+    }
+    return true;
+}
+
+?>
\ No newline at end of file
diff --git a/html/inc/util.inc b/html/inc/util.inc
index 9e5d55abaa..aaebf28d04 100644
--- a/html/inc/util.inc
+++ b/html/inc/util.inc
@@ -987,29 +987,6 @@ function version_string_maj_min_rel($v) {
     return sprintf("%d.%d.%d", $maj, $min, $v);
 }
 
-// recaptcha utilities
-
-function recaptcha_get_head_extra() {
-    // are we using recaptcha?
-    $publickey = parse_config(get_config(), "<recaptcha_public_key>");
-    if ($publickey) {
-        // the meta tag must be included
-        // for Recaptcha to work with some IE browsers
-        return '<meta http-equiv="X-UA-Compatible" content="IE=EmulateIE8" >
-        <script src="https://www.google.com/recaptcha/api.js" async defer></script>';
-    } else {
-        return null;
-    }
-}
-
-function boinc_recaptcha_get_html($publickey) {
-    if ($publickey) {
-        return '<div class="g-recaptcha" data-sitekey="' . $publickey . '"></div>';
-    } else {
-        return '';
-    }
-}
-
 $cvs_version_tracker[]="\$Id$";  //Generated automatically - do not edit
 
 ?>
diff --git a/html/user/create_account_action.php b/html/user/create_account_action.php
index d5e7a78e69..a5a961fde9 100644
--- a/html/user/create_account_action.php
+++ b/html/user/create_account_action.php
@@ -40,9 +40,7 @@ if (parse_bool($config, "disable_account_creation")
 
 $privatekey = parse_config($config, "<recaptcha_private_key>");
 if ($privatekey) {
-    $recaptcha = new ReCaptcha($privatekey);
-    $resp = $recaptcha->verifyResponse($_SERVER["REMOTE_ADDR"], $_POST["g-recaptcha-response"]);
-    if (!$resp->success) {
+    if (!boinc_recaptcha_isValidated($privatekey)) {
         show_error(tra("Your reCAPTCHA response was not correct. Please try again."));
     }
 }
diff --git a/html/user/create_account_form.php b/html/user/create_account_form.php
index 630f630c28..467aa39084 100644
--- a/html/user/create_account_form.php
+++ b/html/user/create_account_form.php
@@ -38,7 +38,7 @@ if (parse_bool($config, "no_web_account_creation")) {
     error_page("This project has disabled Web account creation");
 }
 
-page_head(tra("Create an account"), null, null, null, recaptcha_get_head_extra());
+page_head(tra("Create an account"), null, null, null, boinc_recaptcha_get_head_extra());
 
 if (!no_computing()) {
     echo "<p>
diff --git a/html/user/create_profile.php b/html/user/create_profile.php
index 9d2d4d69f4..7b549a7853 100644
--- a/html/user/create_profile.php
+++ b/html/user/create_profile.php
@@ -20,6 +20,7 @@
 
 require_once("../inc/profile.inc");
 require_once("../inc/akismet.inc");
+require_once("../inc/recaptchalib.php");
 
 if (DISABLE_PROFILES) error_page("Profiles are disabled");
 
@@ -200,9 +201,7 @@ function process_create_profile($user, $profile) {
 
     $privatekey = parse_config($config, "<recaptcha_private_key>");
     if ($privatekey) {
-        $recaptcha = new ReCaptcha($privatekey);
-        $resp = $recaptcha->verifyResponse($_SERVER["REMOTE_ADDR"], $_POST["g-recaptcha-response"]);
-        if (!$resp->success) {
+        if (!boinc_recaptcha_isValidated($privatekey)) {
             $profile->response1 = $response1;
             $profile->response2 = $response2;
             show_profile_form($profile,
@@ -314,9 +313,9 @@ function process_create_profile($user, $profile) {
 
 function show_profile_form($profile, $warning=null) {
     if ($profile) {
-        page_head(tra("Edit your profile"), null, null, null, recaptcha_get_head_extra());
+        page_head(tra("Edit your profile"), null, null, null, boinc_recaptcha_get_head_extra());
     } else {
-        page_head(tra("Create a profile"), null, null, null, recaptcha_get_head_extra());
+        page_head(tra("Create a profile"), null, null, null, boinc_recaptcha_get_head_extra());
     }
 
     if ($warning) {
diff --git a/py/Boinc/setup_project.py b/py/Boinc/setup_project.py
index 0cefe9d27d..ea0a7a9ad6 100644
--- a/py/Boinc/setup_project.py
+++ b/py/Boinc/setup_project.py
@@ -263,6 +263,8 @@ def create_project_dirs(dest_dir):
             'html',
             'html/cache',
             'html/inc',
+            'html/inc/ReCaptcha',
+            'html/inc/ReCaptcha/RequestMethod',
             'html/languages',
             'html/languages/compiled',
             'html/languages/translations',
@@ -314,6 +316,8 @@ def install_boinc_files(dest_dir, install_web_files, install_server_files):
     if install_web_files:
         install_glob(srcdir('html/inc/*.inc'), dir('html/inc/'))
         install_glob(srcdir('html/inc/*.php'), dir('html/inc/'))
+        install_glob(srcdir('html/inc/ReCaptcha/*.php'), dir('html/inc/ReCaptcha/'))
+        install_glob(srcdir('html/inc/ReCaptcha/RequestMethod/*.php'), dir('html/inc/ReCaptcha/RequestMethod'))
         install_glob(srcdir('html/inc/*.dat'), dir('html/inc/'))
         install_glob(srcdir('html/ops/*.css'), dir('html/ops/'))
         install_glob(srcdir('html/ops/ffmail/sample*'), dir('html/ops/ffmail/'))