From 0085e272b2002437f11f74ccdde0d6975f2cd9f2 Mon Sep 17 00:00:00 2001 From: Starla Insigna Date: Tue, 17 Aug 2010 13:40:52 -0400 Subject: Added back reCAPTCHA Because of the lifting of the jail around my server, it can once again use reCAPTCHAs for security. Backed out changeset 9332c237adcd --- includes/recaptchalib.php | 277 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 277 insertions(+) create mode 100755 includes/recaptchalib.php (limited to 'includes/recaptchalib.php') diff --git a/includes/recaptchalib.php b/includes/recaptchalib.php new file mode 100755 index 0000000..897c509 --- /dev/null +++ b/includes/recaptchalib.php @@ -0,0 +1,277 @@ + $value ) + $req .= $key . '=' . urlencode( stripslashes($value) ) . '&'; + + // Cut the last '&' + $req=substr($req,0,strlen($req)-1); + return $req; +} + + + +/** + * Submits an HTTP POST to a reCAPTCHA server + * @param string $host + * @param string $path + * @param array $data + * @param int port + * @return array response + */ +function _recaptcha_http_post($host, $path, $data, $port = 80) { + + $req = _recaptcha_qsencode ($data); + + $http_request = "POST $path HTTP/1.0\r\n"; + $http_request .= "Host: $host\r\n"; + $http_request .= "Content-Type: application/x-www-form-urlencoded;\r\n"; + $http_request .= "Content-Length: " . strlen($req) . "\r\n"; + $http_request .= "User-Agent: reCAPTCHA/PHP\r\n"; + $http_request .= "\r\n"; + $http_request .= $req; + + $response = ''; + if( false == ( $fs = @fsockopen($host, $port, $errno, $errstr, 10) ) ) { + die ('Could not open socket'); + } + + fwrite($fs, $http_request); + + while ( !feof($fs) ) + $response .= fgets($fs, 1160); // One TCP-IP packet + fclose($fs); + $response = explode("\r\n\r\n", $response, 2); + + return $response; +} + + + +/** + * Gets the challenge HTML (javascript and non-javascript version). + * This is called from the browser, and the resulting reCAPTCHA HTML widget + * is embedded within the HTML form it was called from. + * @param string $pubkey A public key for reCAPTCHA + * @param string $error The error given by reCAPTCHA (optional, default is null) + * @param boolean $use_ssl Should the request be made over ssl? (optional, default is false) + + * @return string - The HTML to be embedded in the user's form. + */ +function recaptcha_get_html ($pubkey, $error = null, $use_ssl = false) +{ + if ($pubkey == null || $pubkey == '') { + die ("To use reCAPTCHA you must get an API key from http://recaptcha.net/api/getkey"); + } + + if ($use_ssl) { + $server = RECAPTCHA_API_SECURE_SERVER; + } else { + $server = RECAPTCHA_API_SERVER; + } + + $errorpart = ""; + if ($error) { + $errorpart = "&error=" . $error; + } + return ' + + '; +} + + + + +/** + * A ReCaptchaResponse is returned from recaptcha_check_answer() + */ +class ReCaptchaResponse { + var $is_valid; + var $error; +} + + +/** + * Calls an HTTP POST function to verify if the user's guess was correct + * @param string $privkey + * @param string $remoteip + * @param string $challenge + * @param string $response + * @param array $extra_params an array of extra variables to post to the server + * @return ReCaptchaResponse + */ +function recaptcha_check_answer ($privkey, $remoteip, $challenge, $response, $extra_params = array()) +{ + if ($privkey == null || $privkey == '') { + die ("To use reCAPTCHA you must get an API key from http://recaptcha.net/api/getkey"); + } + + if ($remoteip == null || $remoteip == '') { + die ("For security reasons, you must pass the remote ip to reCAPTCHA"); + } + + + + //discard spam submissions + if ($challenge == null || strlen($challenge) == 0 || $response == null || strlen($response) == 0) { + $recaptcha_response = new ReCaptchaResponse(); + $recaptcha_response->is_valid = false; + $recaptcha_response->error = 'incorrect-captcha-sol'; + return $recaptcha_response; + } + + $response = _recaptcha_http_post (RECAPTCHA_VERIFY_SERVER, "/verify", + array ( + 'privatekey' => $privkey, + 'remoteip' => $remoteip, + 'challenge' => $challenge, + 'response' => $response + ) + $extra_params + ); + + $answers = explode ("\n", $response [1]); + $recaptcha_response = new ReCaptchaResponse(); + + if (trim ($answers [0]) == 'true') { + $recaptcha_response->is_valid = true; + } + else { + $recaptcha_response->is_valid = false; + $recaptcha_response->error = $answers [1]; + } + return $recaptcha_response; + +} + +/** + * gets a URL where the user can sign up for reCAPTCHA. If your application + * has a configuration page where you enter a key, you should provide a link + * using this function. + * @param string $domain The domain where the page is hosted + * @param string $appname The name of your application + */ +function recaptcha_get_signup_url ($domain = null, $appname = null) { + return "http://recaptcha.net/api/getkey?" . _recaptcha_qsencode (array ('domain' => $domain, 'app' => $appname)); +} + +function _recaptcha_aes_pad($val) { + $block_size = 16; + $numpad = $block_size - (strlen ($val) % $block_size); + return str_pad($val, strlen ($val) + $numpad, chr($numpad)); +} + +/* Mailhide related code */ + +function _recaptcha_aes_encrypt($val,$ky) { + if (! function_exists ("mcrypt_encrypt")) { + die ("To use reCAPTCHA Mailhide, you need to have the mcrypt php module installed."); + } + $mode=MCRYPT_MODE_CBC; + $enc=MCRYPT_RIJNDAEL_128; + $val=_recaptcha_aes_pad($val); + return mcrypt_encrypt($enc, $ky, $val, $mode, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"); +} + + +function _recaptcha_mailhide_urlbase64 ($x) { + return strtr(base64_encode ($x), '+/', '-_'); +} + +/* gets the reCAPTCHA Mailhide url for a given email, public key and private key */ +function recaptcha_mailhide_url($pubkey, $privkey, $email) { + if ($pubkey == '' || $pubkey == null || $privkey == "" || $privkey == null) { + die ("To use reCAPTCHA Mailhide, you have to sign up for a public and private key, " . + "you can do so at http://mailhide.recaptcha.net/apikey"); + } + + + $ky = pack('H*', $privkey); + $cryptmail = _recaptcha_aes_encrypt ($email, $ky); + + return "http://mailhide.recaptcha.net/d?k=" . $pubkey . "&c=" . _recaptcha_mailhide_urlbase64 ($cryptmail); +} + +/** + * gets the parts of the email to expose to the user. + * eg, given johndoe@example,com return ["john", "example.com"]. + * the email is then displayed as john...@example.com + */ +function _recaptcha_mailhide_email_parts ($email) { + $arr = preg_split("/@/", $email ); + + if (strlen ($arr[0]) <= 4) { + $arr[0] = substr ($arr[0], 0, 1); + } else if (strlen ($arr[0]) <= 6) { + $arr[0] = substr ($arr[0], 0, 3); + } else { + $arr[0] = substr ($arr[0], 0, 4); + } + return $arr; +} + +/** + * Gets html to display an email address given a public an private key. + * to get a key, go to: + * + * http://mailhide.recaptcha.net/apikey + */ +function recaptcha_mailhide_html($pubkey, $privkey, $email) { + $emailparts = _recaptcha_mailhide_email_parts ($email); + $url = recaptcha_mailhide_url ($pubkey, $privkey, $email); + + return htmlentities($emailparts[0]) . "...@" . htmlentities ($emailparts [1]); + +} + + +?> -- cgit 1.4.1