code: protected function validator($varInput)
  	{
  		$this->blnSubmitInput = false;
  
  		if (!\strlen($varInput) && (\strlen($this->varValue) || !$this->mandatory))
  		{
  			return '';
  		}
  
  		// Check password length either from DCA or use Config as fallback (#1087)
  		$intLength = $this->minlength ?: Config::get('minPasswordLength');
  
  		if (Utf8::strlen($varInput) < $intLength)
  		{
  			$this->addError(sprintf($GLOBALS['TL_LANG']['ERR']['passwordLength'], $intLength));
  		}
  
  		if ($varInput != $this->getPost($this->strName . '_confirm'))
  		{
  			$this->addError($GLOBALS['TL_LANG']['ERR']['passwordMatch']);
  		}
  
  		$varInput = parent::validator($varInput);
  
  		if (!$this->hasErrors())
  		{
  			$this->blnSubmitInput = true;
  
  			return password_hash($varInput, PASSWORD_DEFAULT);
  		}
  
  		return '';
  	}
docs: Validate input and set value
  
  @param mixed $varInput The user input
  
  @return mixed The validated user input