64 lines
1.4 KiB
PHP
64 lines
1.4 KiB
PHP
<?php
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/**
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* Captcha logic class
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*/
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include_once(dirname(__FILE__).'/./config.inc.php');
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class Captcha {
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private $calcOps;
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function __construct() {
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$this->calcOps = array("+", "-", "*");
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}
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function generateAndUseCaptcha() {
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$rndType = rand(1, 100);
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if ($rndType > 0) {
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// build numeric question
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$useOp = $this->calcOps[rand(0, 2)];
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$firstNum = 0;
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$secondNum = 0;
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if ($useOp == "*") {
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$firstNum = rand(0, 9);
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$secondNum = rand(0, 15);
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} else {
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$firstNum = rand(0, 100);
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$secondNum = rand(0, 100);
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}
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$calc = 0;
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if ($useOp == "+") {
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$calc = $firstNum + $secondNum;
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} else if ($useOp == "-") {
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$calc = $firstNum - $secondNum;
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} else if ($useOp == "*") {
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$calc = $firstNum * $secondNum;
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}
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$mathStr = "" . $firstNum . " " . $useOp . " " . $secondNum;
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$_SESSION['CAPTCHA_QUESTION'] = $mathStr;
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$_SESSION['CAPTCHA_VALUE'] = $calc;
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// field name
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$fieldname = chr(rand(65, 90)) . dechex(rand());
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$_SESSION['CAPTCHA_FIELD'] = $fieldname;
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return $mathStr;
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} else {
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// use pooled question
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// TODO currently not supported due to missing logic which language to use
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}
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}
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function validateCaptcha($inputStr) {
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if (empty($inputStr) == true) {
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return false;
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}
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if (isset($_SESSION['CAPTCHA_VALUE']) == false) {
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return false;
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}
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$valueInSession = $_SESSION['CAPTCHA_VALUE'];
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return ($inputStr == $valueInSession . "");
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}
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}
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