<?php
function decrypt_and_get_counter() {
    $iv = str_repeat("\x00", 16); // Initialisierungsvektor
    $key = str_repeat("\x00", 16); // AES-Schlüssel
    $picc = "CACDEC6C5455EE52BB1DA40470963113"; // Hexadezimale Eingabe
 
    // Konvertiere die Eingabe von Hex in Binär
    $picc_binary = hex2bin($picc);
    if ($picc_binary === false) {
        die("Ungültige Hex-Eingabe");
    }
 
    // Entschlüsselung mit AES-128 im CBC-Modus
    $decrypted = openssl_decrypt(
        $picc_binary,
        'aes-128-cbc',
        $key,
        OPENSSL_RAW_DATA,
        $iv
    );
 
    if ($decrypted === false) {
        die("Entschlüsselung fehlgeschlagen");
    }
 
    // Extrahiere den Zähler aus den Bytes 9 und 8
    $counter = unpack('v', substr($decrypted, 8, 2)); // Little-Endian-Entpacken
    if ($counter === false) {
        die("Konnte den Zähler nicht extrahieren");
    }
 
    $counter_value = $counter[1];
 
    echo "hallo\n";
    echo $counter_value . "\n";
    echo "hallo\n";
}
 
// Führe die Funktion aus
decrypt_and_get_counter();
?>

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