Trustworthy Software Reliability Research Based on UNIX Login Packet Security Analysis

As the modern society becomes increasingly dependent on software, how to develop Trustworthy Software(TS) systems is considered a critical issue by academia, government and industry. The domain of our work focused on the reliability research on UNIX system, which is the famous and widely used operation system in the world, and adopts C/S software architecture. However, when the user remote login the UNIX system, the login packets that contain private messages such as account and password easily captured and cracked by the hackers because they are transmitting in the network without encryption. Firstly, we review the main principle of packet capture technology. Then to aim at UNIX remote login packet, we give a detailed case to illustrate the whole process to invade UNIX successfully. The process consists of following steps: how to use packet capture technology to capture it illegally in the network, how to further analysis its´ frame structure, how to obtain the secret information without user authorization by deciphering it. They are also the innovations of this article. Finally, we give some suggestions on preventing from and striking back packet capture to satisfy the reliability system requirements.