<?php
require_once('Aes128CBCEncryptor.php');
echo PHP_EOL.PHP_EOL.PHP_EOL;
echo 'Padding oracle attack' . PHP_EOL .PHP_EOL;
//echo "Tekst: ";
//$text = fgets(STDIN);

$text = "Kryptologia to najfajniejszy kurs w roku 2019/2020 119WI2";
echo "Tekst: " . PHP_EOL;
echo $text . PHP_EOL .PHP_EOL;

$cipheredText = Aes128CBCEncryptor::encrypt($text);
echo "Zaszyfrowany tekst: " . PHP_EOL;
foreach (str_split($cipheredText, Aes128CBCEncryptor::BLOCK_SIZE) as $block) {
    echo base64_encode($block) . PHP_EOL;
}

echo PHP_EOL. '--------' . PHP_EOL .PHP_EOL;
$blocks = str_split($cipheredText, Aes128CBCEncryptor::BLOCK_SIZE);
$blockCount = count($blocks);
$plainText = '';

for ($i = 0; $i < $blockCount; $i++) {
    if ($blockCount - ($i+2) >= 0) {
        $C = 'aaaaaaaaaaaaaaa';
        $lastXORs = [];
        for ($k = 1; $k <= Aes128CBCEncryptor::BLOCK_SIZE; $k++) {
            for ($m = 1; $m < $k; $m++) {
                $C[Aes128CBCEncryptor::BLOCK_SIZE - $m] = chr($k ^ $lastXORs[$m-1]);
            }
            for ($j = 0; $j < 256; $j++) {
                $C[Aes128CBCEncryptor::BLOCK_SIZE - $k] = chr($j);
                if (Aes128CBCEncryptor::paddingOracleCheck($C . $blocks[$blockCount - ($i+1)])) {
                    $paddingXor = ($k ^ $j);
                    $lastXORs[] = $paddingXor;
                    $decipheredLetter = (ord($blocks[$blockCount - ($i+2)][Aes128CBCEncryptor::BLOCK_SIZE - $k]) ^ $paddingXor);
                    $plainText = chr($decipheredLetter) . $plainText;
                    continue;
                }
            }
        }
    }
    $plainText = PHP_EOL . $plainText;
}
echo 'Odszyfrowane bloki: ';
echo $plainText;