php加密解密算法

/**
	 * 解密
	 * 
	 * @param string $encryptedText 已加密字符串
	 * @param string $key  密钥
	 * @return string
	 */
	private  function _decrypt($encryptedText,$key)
	{
		$cryptText = base64_decode($encryptedText);
		$ivSize = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);
		$iv = mcrypt_create_iv($ivSize, MCRYPT_RAND);
		$decryptText = mcrypt_decrypt(MCRYPT_RIJNDAEL_256, $key, $cryptText, MCRYPT_MODE_ECB, $iv);
		return trim($decryptText);
	}

/**
	 * 加密
	 *
	 * @param string $plainText	未加密字符串 
	 * @param string $key		 密钥
	 */
	private function _encrypt($plainText,$key){
		$ivSize      = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);
		$iv          = mcrypt_create_iv($ivSize, MCRYPT_RAND);
		$encryptText = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, $key, $plainText, MCRYPT_MODE_ECB, $iv);
		return trim(base64_encode($encryptText));
	}