<?php
/**
* This is a PHP library that handles calling reCAPTCHA.
*
* BSD 3-Clause License
* @copyright (c) 2019, Google Inc.
* @link https://www.google.com/recaptcha
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
namespace ReCaptcha;
/**
* reCAPTCHA client.
*/
class ReCaptcha
{
/**
* Version of this client library.
* @const string
*/
const VERSION = 'php_1.2.4';
/**
* URL for reCAPTCHA siteverify API
* @const string
*/
const SITE_VERIFY_URL = 'https://www.google.com/recaptcha/api/siteverify';
/**
* Invalid JSON received
* @const string
*/
const E_INVALID_JSON = 'invalid-json';
/**
* Could not connect to service
* @const string
*/
const E_CONNECTION_FAILED = 'connection-failed';
/**
* Did not receive a 200 from the service
* @const string
*/
const E_BAD_RESPONSE = 'bad-response';
/**
* Not a success, but no error codes received!
* @const string
*/
const E_UNKNOWN_ERROR = 'unknown-error';
/**
* ReCAPTCHA response not provided
* @const string
*/
const E_MISSING_INPUT_RESPONSE = 'missing-input-response';
/**
* Expected hostname did not match
* @const string
*/
const E_HOSTNAME_MISMATCH = 'hostname-mismatch';
/**
* Expected APK package name did not match
* @const string
*/
const E_APK_PACKAGE_NAME_MISMATCH = 'apk_package_name-mismatch';
/**
* Expected action did not match
* @const string
*/
const E_ACTION_MISMATCH = 'action-mismatch';
/**
* Score threshold not met
* @const string
*/
const E_SCORE_THRESHOLD_NOT_MET = 'score-threshold-not-met';
/**
* Challenge timeout
* @const string
*/
const E_CHALLENGE_TIMEOUT = 'challenge-timeout';
/**
* Shared secret for the site.
* @var string
*/
private $secret;
/**
* Method used to communicate with service. Defaults to POST request.
* @var RequestMethod
*/
private $requestMethod;
/**
* @var string
*/
private $hostname;
/**
* @var string
*/
private $apkPackageName;
/**
* @var string
*/
private $action;
/**
* @var float
*/
private $threshold;
/**
* @var int
*/
private $timeoutSeconds;
/**
* Create a configured instance to use the reCAPTCHA service.
*
* @param string $secret The shared key between your site and reCAPTCHA.
* @param RequestMethod $requestMethod method used to send the request. Defaults to POST.
* @throws \RuntimeException if $secret is invalid
*/
public function __construct($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;
$this->requestMethod = (is_null($requestMethod)) ? new RequestMethod\Post() : $requestMethod;
}
/**
* Calls the reCAPTCHA siteverify API to verify whether the user passes
* CAPTCHA test and additionally runs any specified additional checks
*
* @param string $response The user response token provided by reCAPTCHA, verifying the user on your site.
* @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)) {
return new Response(false, array(self::E_MISSING_INPUT_RESPONSE));
}
$params = new RequestParameters($this->secret, $response, $remoteIp, self::VERSION);
$rawResponse = $this->requestMethod->submit($params);
$initialResponse = Response::fromJson($rawResponse);
$validationErrors = array();
if (isset($this->hostname) && strcasecmp($this->hostname, $initialResponse->getHostname()) !== 0) {
$validationErrors[] = self::E_HOSTNAME_MISMATCH;
}
if (isset($this->apkPackageName) && strcasecmp($this->apkPackageName, $initialResponse->getApkPackageName()) !== 0) {
$validationErrors[] = self::E_APK_PACKAGE_NAME_MISMATCH;
}
if (isset($this->action) && strcasecmp($this->action, $initialResponse->getAction()) !== 0) {
$validationErrors[] = self::E_ACTION_MISMATCH;
}
if (isset($this->threshold) && $this->threshold > $initialResponse->getScore()) {
$validationErrors[] = self::E_SCORE_THRESHOLD_NOT_MET;
}
if (isset($this->timeoutSeconds)) {
$challengeTs = strtotime($initialResponse->getChallengeTs());
if ($challengeTs > 0 && time() - $challengeTs > $this->timeoutSeconds) {
$validationErrors[] = self::E_CHALLENGE_TIMEOUT;
}
}
if (empty($validationErrors)) {
return $initialResponse;
}
return new Response(
false,
array_merge($initialResponse->getErrorCodes(), $validationErrors),
$initialResponse->getHostname(),
$initialResponse->getChallengeTs(),
$initialResponse->getApkPackageName(),
$initialResponse->getScore(),
$initialResponse->getAction()
);
}
/**
* Provide a hostname to match against in verify()
* This should be without a protocol or trailing slash, e.g. www.google.com
*
* @param string $hostname Expected hostname
* @return ReCaptcha Current instance for fluent interface
*/
public function setExpectedHostname($hostname)
{
$this->hostname = $hostname;
return $this;
}
/**
* Provide an APK package name to match against in verify()
*
* @param string $apkPackageName Expected APK package name
* @return ReCaptcha Current instance for fluent interface
*/
public function setExpectedApkPackageName($apkPackageName)
{
$this->apkPackageName = $apkPackageName;
return $this;
}
/**
* Provide an action to match against in verify()
* This should be set per page.
*
* @param string $action Expected action
* @return ReCaptcha Current instance for fluent interface
*/
public function setExpectedAction($action)
{
$this->action = $action;
return $this;
}
/**
* Provide a threshold to meet or exceed in verify()
* Threshold should be a float between 0 and 1 which will be tested as response >= threshold.
*
* @param float $threshold Expected threshold
* @return ReCaptcha Current instance for fluent interface
*/
public function setScoreThreshold($threshold)
{
$this->threshold = floatval($threshold);
return $this;
}
/**
* Provide a timeout in seconds to test against the challenge timestamp in verify()
*
* @param int $timeoutSeconds Expected hostname
* @return ReCaptcha Current instance for fluent interface
*/
public function setChallengeTimeout($timeoutSeconds)
{
$this->timeoutSeconds = $timeoutSeconds;
return $this;
}
}