Author Archives: cormander

Repacking an RPM from files on the system

Have you ever had an RPM installed on the system that you needed installed on another system, but didn’t have the .rpm file for it? Or, have you wanted to make a .rpm file with just a minor change without … Continue reading

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You can find my stuff on GitHub

I’ve been using GitHub a lot more lately, and have found it to be a great service. So, this is me officially saying that any code I reference you should be able to find in one of my github repositories. … Continue reading

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nagios snmp check all disks plugin

Having to manage a wide array of servers with vastly different disk configurations, I found that things began to be very tedious with the nagios configuration file for disks checks. It seemed as if no two server disk configuration was … Continue reading

Posted in Fun, Linux, nagios | 1 Comment

How to hook into (hijack) linux kernel functions via LKM

It’s about time I post a detailed explanation about how my tpe-lkm module is able to enforce its security policy. This post is very technical, readers beware. Note that this writeup is based on the code as it was the … Continue reading

Posted in Fun, ksplice, Linux, Security | Leave a comment

How I license code

If you’ve looked at any of my original code lately, you might have noticed how I license it at the top of said code: # # Originally written by Corey Henderson # # Dual-Licensed – you may choose between: # … Continue reading

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Monitor time drift with nagios and snmp

The other day I threw together a check_snmp_time.pl script that simply checks the remote’s time against the monitor host’s time. It’s fairly straight forward, and will alert you when host’s time drift too much, indicating that your ntpd configuration is … Continue reading

Posted in Linux, nagios | 1 Comment

An agent, auditor, and bodyguard walk into a bar…

This evening I wasted a bunch of time on what turned out to be a simple problem. I really hate it when that happens. I fixed a bug in tpe-lkm where users weren’t seeing all of their processes, and updated … Continue reading

Posted in Complaints, Linux, nagios | Leave a comment

tpe-lkm “hardcoded_path” feature

This evening I implemented the optional hardcoded_path feature for tpe-lkm. It’s a way to be very strict on what on the system can be executed. When set, anything outside of the given path can’t be executed, regardless of permissions or … Continue reading

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tpe-lkm “lock” sysctl feature

Tonight I implemented a “lock” sysctl feature for tpe-lkm. When enabled, the sysctl entries for the tpe module can’t be changed. It’s only real useful if also combined with the modules_disabled option.

Posted in Linux, Security | 1 Comment

My first book review starts today

Last week I completed the first draft of Part 1 of my book on Linux Security (chapters 1 through 4). I just got word that it’s been sent out for review, and expect to get them back in a few … Continue reading

Posted in Book Writing, Notices | Leave a comment