Gee Law’s Blog

The Code Book (Simon Singh) 读书笔记

操作系统课中讲安全的一节是代课老师上的,期间他推荐了 The Code Book (Simon Singh) 这本书,说是讲密码学历史的。我对密码学感兴趣,就读了一读,并照“不动笔墨不读书”的原则,记了读书笔记,发表出来以飨观众。

The Code Book (Simon Singh) 读书笔记

如何在操统课 Bitcoin 大作业组间比赛歇菜

交叉信息研究院的本科生操作系统课程的大作业很奇特,并不是 4 个 NachOS 作业,而是两次 NachOS、两次分布式数据库。最后一次大作业是要写一个 Bitcoin 挖矿程序,而且还有组间比赛,各个小组的矿机和客户端会一起运行一段时间,最终获得最高手续费的矿机会获胜。

如何在操统课 Bitcoin 大作业组间比赛歇菜

Windows Credential User Interface with secure attention sequence: not even bad

Ever since I used Windows NT (for me, the first Windows NT I used is Windows XP), I’ve been familiar with the importance of Ctrl+Alt+Delete. The combination is known as the secure attention sequence for Windows. In an uninfected copy of Windows, the sequence is handled exclusively by Windows, and is used to thwart trojan dialogs luring users’ credentials. Requiring SAS before Welcome Screen is a quite usable security feature. However, it is not the case for Credential User Interface.

NTFS DELETE_CHILD access and ‘the directory is not empty’

Someone wanted to know how to create a file that denies itself from being removed, yet found he could still remove the file even denying DELETE access from Everyone. The reason is that there is DELETE_CHILD access on its containing directory. How does this relate to ‘the directory is not empty’?