Edward Linus's personal blog, focusing on coding and etc.


In this category, I share notes I take from learning something, hope that it will help you on some problems.

Utilizing fail2ban to Protect SSHD & Mail Service on CentOS


0x00 STORY I haven’t checked mail log after installing dovecot and postfix, since these mailing services runs well without any problem, but recently I found issue on losing mails when sending numerous mails at the same time, then I looked into dovecot and postfix’s configuration thoroughly, however, everything seems to be ok, then I turned to check mail log hoping to find some errors...

An Introduction to DELAUNEY Triangulation


0x01 Introduction Recently I’m working on visualization of flow velocity pulsation, it is necessary to draw a contour map of the distribution of the velocity pulsation intensity on the cross section. The Chart control provided by Winform does not provide the function of contour drawing. So I look up in Baidu for some information, and probably learned the steps of contour drawing, and I will...

Building a lite private cloud disk with aria2 and File Browser


0x00 Introduction Cloud disk providers like baidu, 115, yunfile have provided us with convenient cloud storage services which enables us to gain access to file across multiple platforms and devices. Since our works are often related to word, excel, ppt and etc, we rely heavily on a desktop or laptop to produce productivity in our routine life, but there’s always sometime we don’t have...

DrCOM(ver.D) in HHU Packet Analysis


0x00 Packet List Challenge Login Logout KeepAlive_1 KeepAlive_2 0x01 Login & Logout Route 0x011 Login Route First, a chanllange packet is made and sent to server, and the response should start with 0x02 and contain 4 bytes salt at the offset 0x14. Second, a login packet can be made with the salt we’ve got, after we send it to the server, it should respond with data which starts with...

Monitor Changes in a Website and Push Notification to Slack via Huginn and Slack API


0x00 Story A fellow of mine wants to monitor changes in a website, at first he use a monitor plugin in chrome, but before long he realized that he cannot keep his computer running all the time, therefore to use an VPS to monitor  is a pretty decent choice. Here comes the question, what software should we use? It comes to me that I can use Python to write a crawler, but I’m too lazy to...

Edward Linus's personal blog, focusing on coding and etc.