Process form submissions into templated emails.

recaptchalib.php 9.5KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277
  1. <?php
  2. /*
  3. * This is a PHP library that handles calling reCAPTCHA.
  4. * - Documentation and latest version
  5. * http://recaptcha.net/plugins/php/
  6. * - Get a reCAPTCHA API Key
  7. * http://recaptcha.net/api/getkey
  8. * - Discussion group
  9. * http://groups.google.com/group/recaptcha
  10. *
  11. * Copyright (c) 2007 reCAPTCHA -- http://recaptcha.net
  12. * AUTHORS:
  13. * Mike Crawford
  14. * Ben Maurer
  15. *
  16. * Permission is hereby granted, free of charge, to any person obtaining a copy
  17. * of this software and associated documentation files (the "Software"), to deal
  18. * in the Software without restriction, including without limitation the rights
  19. * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  20. * copies of the Software, and to permit persons to whom the Software is
  21. * furnished to do so, subject to the following conditions:
  22. *
  23. * The above copyright notice and this permission notice shall be included in
  24. * all copies or substantial portions of the Software.
  25. *
  26. * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  27. * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  28. * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  29. * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  30. * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  31. * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  32. * THE SOFTWARE.
  33. */
  34. /**
  35. * The reCAPTCHA server URL's
  36. */
  37. define("RECAPTCHA_API_SERVER", "http://api.recaptcha.net");
  38. define("RECAPTCHA_API_SECURE_SERVER", "https://api-secure.recaptcha.net");
  39. define("RECAPTCHA_VERIFY_SERVER", "api-verify.recaptcha.net");
  40. /**
  41. * Encodes the given data into a query string format
  42. * @param $data - array of string elements to be encoded
  43. * @return string - encoded request
  44. */
  45. function _recaptcha_qsencode ($data) {
  46. $req = "";
  47. foreach ( $data as $key => $value )
  48. $req .= $key . '=' . urlencode( stripslashes($value) ) . '&';
  49. // Cut the last '&'
  50. $req=substr($req,0,strlen($req)-1);
  51. return $req;
  52. }
  53. /**
  54. * Submits an HTTP POST to a reCAPTCHA server
  55. * @param string $host
  56. * @param string $path
  57. * @param array $data
  58. * @param int port
  59. * @return array response
  60. */
  61. function _recaptcha_http_post($host, $path, $data, $port = 80) {
  62. $req = _recaptcha_qsencode ($data);
  63. $http_request = "POST $path HTTP/1.0\r\n";
  64. $http_request .= "Host: $host\r\n";
  65. $http_request .= "Content-Type: application/x-www-form-urlencoded;\r\n";
  66. $http_request .= "Content-Length: " . strlen($req) . "\r\n";
  67. $http_request .= "User-Agent: reCAPTCHA/PHP\r\n";
  68. $http_request .= "\r\n";
  69. $http_request .= $req;
  70. $response = '';
  71. if( false == ( $fs = @fsockopen($host, $port, $errno, $errstr, 10) ) ) {
  72. die ('Could not open socket');
  73. }
  74. fwrite($fs, $http_request);
  75. while ( !feof($fs) )
  76. $response .= fgets($fs, 1160); // One TCP-IP packet
  77. fclose($fs);
  78. $response = explode("\r\n\r\n", $response, 2);
  79. return $response;
  80. }
  81. /**
  82. * Gets the challenge HTML (javascript and non-javascript version).
  83. * This is called from the browser, and the resulting reCAPTCHA HTML widget
  84. * is embedded within the HTML form it was called from.
  85. * @param string $pubkey A public key for reCAPTCHA
  86. * @param string $error The error given by reCAPTCHA (optional, default is null)
  87. * @param boolean $use_ssl Should the request be made over ssl? (optional, default is false)
  88. * @return string - The HTML to be embedded in the user's form.
  89. */
  90. function recaptcha_get_html ($pubkey, $error = null, $use_ssl = false)
  91. {
  92. if ($pubkey == null || $pubkey == '') {
  93. die ("To use reCAPTCHA you must get an API key from <a href='http://recaptcha.net/api/getkey'>http://recaptcha.net/api/getkey</a>");
  94. }
  95. if ($use_ssl) {
  96. $server = RECAPTCHA_API_SECURE_SERVER;
  97. } else {
  98. $server = RECAPTCHA_API_SERVER;
  99. }
  100. $errorpart = "";
  101. if ($error) {
  102. $errorpart = "&amp;error=" . $error;
  103. }
  104. return '<script type="text/javascript" src="'. $server . '/challenge?k=' . $pubkey . $errorpart . '"></script>
  105. <noscript>
  106. <iframe src="'. $server . '/noscript?k=' . $pubkey . $errorpart . '" height="300" width="500" frameborder="0"></iframe><br/>
  107. <textarea name="recaptcha_challenge_field" rows="3" cols="40"></textarea>
  108. <input type="hidden" name="recaptcha_response_field" value="manual_challenge"/>
  109. </noscript>';
  110. }
  111. /**
  112. * A ReCaptchaResponse is returned from recaptcha_check_answer()
  113. */
  114. class ReCaptchaResponse {
  115. var $is_valid;
  116. var $error;
  117. }
  118. /**
  119. * Calls an HTTP POST function to verify if the user's guess was correct
  120. * @param string $privkey
  121. * @param string $remoteip
  122. * @param string $challenge
  123. * @param string $response
  124. * @param array $extra_params an array of extra variables to post to the server
  125. * @return ReCaptchaResponse
  126. */
  127. function recaptcha_check_answer ($privkey, $remoteip, $challenge, $response, $extra_params = array())
  128. {
  129. if ($privkey == null || $privkey == '') {
  130. die ("To use reCAPTCHA you must get an API key from <a href='http://recaptcha.net/api/getkey'>http://recaptcha.net/api/getkey</a>");
  131. }
  132. if ($remoteip == null || $remoteip == '') {
  133. die ("For security reasons, you must pass the remote ip to reCAPTCHA");
  134. }
  135. //discard spam submissions
  136. if ($challenge == null || strlen($challenge) == 0 || $response == null || strlen($response) == 0) {
  137. $recaptcha_response = new ReCaptchaResponse();
  138. $recaptcha_response->is_valid = false;
  139. $recaptcha_response->error = 'incorrect-captcha-sol';
  140. return $recaptcha_response;
  141. }
  142. $response = _recaptcha_http_post (RECAPTCHA_VERIFY_SERVER, "/verify",
  143. array (
  144. 'privatekey' => $privkey,
  145. 'remoteip' => $remoteip,
  146. 'challenge' => $challenge,
  147. 'response' => $response
  148. ) + $extra_params
  149. );
  150. $answers = explode ("\n", $response [1]);
  151. $recaptcha_response = new ReCaptchaResponse();
  152. if (trim ($answers [0]) == 'true') {
  153. $recaptcha_response->is_valid = true;
  154. }
  155. else {
  156. $recaptcha_response->is_valid = false;
  157. $recaptcha_response->error = $answers [1];
  158. }
  159. return $recaptcha_response;
  160. }
  161. /**
  162. * gets a URL where the user can sign up for reCAPTCHA. If your application
  163. * has a configuration page where you enter a key, you should provide a link
  164. * using this function.
  165. * @param string $domain The domain where the page is hosted
  166. * @param string $appname The name of your application
  167. */
  168. function recaptcha_get_signup_url ($domain = null, $appname = null) {
  169. return "http://recaptcha.net/api/getkey?" . _recaptcha_qsencode (array ('domain' => $domain, 'app' => $appname));
  170. }
  171. function _recaptcha_aes_pad($val) {
  172. $block_size = 16;
  173. $numpad = $block_size - (strlen ($val) % $block_size);
  174. return str_pad($val, strlen ($val) + $numpad, chr($numpad));
  175. }
  176. /* Mailhide related code */
  177. function _recaptcha_aes_encrypt($val,$ky) {
  178. if (! function_exists ("mcrypt_encrypt")) {
  179. die ("To use reCAPTCHA Mailhide, you need to have the mcrypt php module installed.");
  180. }
  181. $mode=MCRYPT_MODE_CBC;
  182. $enc=MCRYPT_RIJNDAEL_128;
  183. $val=_recaptcha_aes_pad($val);
  184. return mcrypt_encrypt($enc, $ky, $val, $mode, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0");
  185. }
  186. function _recaptcha_mailhide_urlbase64 ($x) {
  187. return strtr(base64_encode ($x), '+/', '-_');
  188. }
  189. /* gets the reCAPTCHA Mailhide url for a given email, public key and private key */
  190. function recaptcha_mailhide_url($pubkey, $privkey, $email) {
  191. if ($pubkey == '' || $pubkey == null || $privkey == "" || $privkey == null) {
  192. die ("To use reCAPTCHA Mailhide, you have to sign up for a public and private key, " .
  193. "you can do so at <a href='http://mailhide.recaptcha.net/apikey'>http://mailhide.recaptcha.net/apikey</a>");
  194. }
  195. $ky = pack('H*', $privkey);
  196. $cryptmail = _recaptcha_aes_encrypt ($email, $ky);
  197. return "http://mailhide.recaptcha.net/d?k=" . $pubkey . "&c=" . _recaptcha_mailhide_urlbase64 ($cryptmail);
  198. }
  199. /**
  200. * gets the parts of the email to expose to the user.
  201. * eg, given johndoe@example,com return ["john", "example.com"].
  202. * the email is then displayed as john...@example.com
  203. */
  204. function _recaptcha_mailhide_email_parts ($email) {
  205. $arr = preg_split("/@/", $email );
  206. if (strlen ($arr[0]) <= 4) {
  207. $arr[0] = substr ($arr[0], 0, 1);
  208. } else if (strlen ($arr[0]) <= 6) {
  209. $arr[0] = substr ($arr[0], 0, 3);
  210. } else {
  211. $arr[0] = substr ($arr[0], 0, 4);
  212. }
  213. return $arr;
  214. }
  215. /**
  216. * Gets html to display an email address given a public an private key.
  217. * to get a key, go to:
  218. *
  219. * http://mailhide.recaptcha.net/apikey
  220. */
  221. function recaptcha_mailhide_html($pubkey, $privkey, $email) {
  222. $emailparts = _recaptcha_mailhide_email_parts ($email);
  223. $url = recaptcha_mailhide_url ($pubkey, $privkey, $email);
  224. return htmlentities($emailparts[0]) . "<a href='" . htmlentities ($url) .
  225. "' onclick=\"window.open('" . htmlentities ($url) . "', '', 'toolbar=0,scrollbars=0,location=0,statusbar=0,menubar=0,resizable=0,width=500,height=300'); return false;\" title=\"Reveal this e-mail address\">...</a>@" . htmlentities ($emailparts [1]);
  226. }
  227. ?>