true,
'secure' => !empty($_SERVER['HTTPS']) && $_SERVER['HTTPS'] !== 'off',
'samesite' => 'Strict',
]);
session_start();
header('Cache-Control: no-store, no-cache, must-revalidate, max-age=0');
header('Pragma: no-cache');
header('Content-Type: image/svg+xml; charset=UTF-8');
header('X-Content-Type-Options: nosniff');
do {
$digits = range(0, 9);
shuffle($digits);
$digits = array_slice($digits, 0, 6);
$positionConflict = false;
foreach ($digits as $index => $digit) {
if ($digit === ($index + 1)) {
$positionConflict = true;
break;
}
}
} while ($positionConflict);
$position = random_int(1, 6);
$_SESSION['captcha_answer'] = (string)$digits[$position - 1];
$_SESSION['captcha_created_at'] = time();
$_SESSION['captcha_attempts'] = (int)($_SESSION['captcha_attempts'] ?? 0);
$digitElements = [];
foreach ($digits as $index => $digit) {
$x = 104 + ($index * 64) + random_int(-3, 3);
$y = 73 + random_int(-4, 4);
$rotation = random_int(-14, 14);
$digitElements[] = sprintf(
'%d',
$x,
$y,
$rotation,
$x,
$y,
$digit
);
}
$noiseLines = [];
for ($i = 0; $i < 10; $i++) {
$noiseLines[] = sprintf(
'',
random_int(12, 505),
random_int(18, 91),
random_int(12, 505),
random_int(18, 91)
);
}
$question = 'Welche Ziffer steht an Stelle ' . $position . '?';
?>