/**
* @see \Fine47\MicroRouter\Interfaces\Encryptor::encryptString()
*/
public function encryptString($data, $asBase64 = false, $randomize = true)
{
$iv = $this->getIV();
// Compute the length of the IV.
$keySize = strlen($iv);
// Size of original data.
$dataSize = strlen($data);
// Static filler.
$staticFiller = chr(self::CHAR_FILL);
// The data that will be encoded is the following:
//
// 4-byte random characters
// TAB character
// 4-byte length (of the original data)
// TAB character
// 4-byte random characters
// TAB character
// original data passed in $data
// TAB character
// padding necessary for the encryption (optional)
// Generate 4-byte random characters.
$string = true === $randomize ? self::randChars(4) : str_repeat($staticFiller, 4);
// Tab character separator.
$string .= "\t";
// Add length of the original data.
$string .= pack('L*', $dataSize) . "\t";
// Generate additional 8-byte random characters.
$string .= true === $randomize ? self::randChars(4) : str_repeat($staticFiller, 4);
// Tab character separator.
$string .= "\t";
// Add original data.
$string .= $data . "\t";
// Is there a salt to be added?
if (is_string($randomize) && !empty($randomize)) {
$string .= $randomize;
$randomize = true;
}
// Now, add any necessary padding so overall data may be encrypted.
while (0 < strlen($string) % $keySize) {
$string .= !$randomize ? $staticFiller : self::randChar();
}
// Prepare encryption buffers.
mcrypt_generic_init($this->module, $this->getSecret(), $iv);
// Encrypt string.
$string = mcrypt_generic($this->module, $string);
// Free resources.
mcrypt_generic_deinit($this->module);
// Turn it into hex if needed.
if (true === $asBase64) {
$string = Base64::encode($string);
}
return $string;
}
/**
* Retrieves the flash data as an encoded string. If there's no data in flash,
* FALSE is returned.
*
* @return string|FALSE encoded flash data, FALSE if empty
*/
public function toString()
{
if (empty($this->newFlash)) {
// No flash data.
return false;
}
// Return encoded flash data.
return Base64::encode(Json::encode($this->newFlash));
}