function decryptAES128ECB($data, $key, $strictPadding = false)
{
$blocks = str_split($data, 16);
foreach ($blocks as &$block) {
$block = _decryptAES128ECB($block, $key);
}
$plaintext = implode($blocks);
try {
return removePKCS7Padding($plaintext);
} catch (Exception $e) {
if ($strictPadding) {
throw $e;
}
return $plaintext;
}
}
$currentPadding = 16 - $attackPosition;
$realBlock[$attackPosition] = $currentPadding ^ $trialByte ^ ord($iv[$attackPosition]);
if ($attackPosition === 0) {
break 2;
}
for ($j = 15; $j >= $attackPosition; $j--) {
$fauxBlock[$j] = $currentPadding + 1 ^ $realBlock[$j] ^ ord($iv[$j]);
}
break;
}
}
}
return implode(array_map('chr', $realBlock));
}
// don't output if we're included into another script.
if (!debug_backtrace()) {
print "Cracking 10 randomly selected ciphertexts:\n";
for ($j = 0; $j < 10; $j++) {
$key = getRandomBytes(16);
$iv = getRandomBytes(16);
$ciphertext = getRandomCiphertext($key, $iv);
$blocks = str_split($ciphertext, 16);
array_unshift($blocks, $iv);
$blockNum = count($blocks) - 1;
for ($i = $blockNum; $i > 0; $i--) {
$blocks[$i] = crackBlock($blocks[$i], $key, $blocks[$i - 1]);
}
array_shift($blocks);
print "{$j}: " . removePKCS7Padding(implode($blocks)) . "\n";
}
}
