This post contains the bare minimums you need to start working with x509 certificates. After reading the post you should have a better idea about the meaning of the different acronyms related with SSL certificates (ASN1, DER, PEM, etc.). You will also have a better understanding of the format of the certificate.

Tools are provided to create your own certificates and also to use the certificates you have created in SSL communications. The information in this article should be valuable in understanding the certificate format and useful if you need to work with certificate parsing, SSL implementations or fuzzing of the related technologies.

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Popularity: 12% [?]

miniconomics.com is an easy-to-use tool designed to manage your personal expenses that we have been developing over the last few months. The key benefits of the tool at this point in time:

• It is alive, changing every day, release early, release often. miniconomics.com is under a never ending churning process.
• It is simple, a no brainer, you have categories and you have expenses, you put expenses in your categories and miniconomics.com gives you all sorts of useful information, stats and nice shinny graphs.
• Is accessible, forget about maintaing a spreadsheet with your data in your home computer or laptop. Use an online service, use it no matter where you are, no matter when, just log in and add your expenses.
• It is as geek as a tool can be. We are still developing it and we are keen on trying all sorts of approaches. We have some cool toughts on plugins and addons that we will be developing in the future. Give us your feedback and let us know what you do you want out of the tool, chances are we will develop it!
• miniconomics.com is free, free to use, free to register, free to enjoy, free to everything

I hope you decide to give it a try (you don’t have to register for a test drive) and let us know what you think. And of course if you like it, just spread the word.

Popularity: 15% [?]

Directly inspired by The Art of War of Sun Tzu, yesterday I found the following piece of wisdom:

After years of thinking about, writing about, and filtering messages, I’ve decided that the best strategy for me is to not filter spam, but instead to filter non-spam

The full article at Reverse Spam Filtering: “Winning Without Fighting” by Nancy McGough.

Popularity: 16% [?]

A new puzzle, this time from Conceptual Blockbusting: A Guide to Better Ideas by Jams L. Adams:

One morning, exactly at sunrise, a Buddhist monk began to climb a tall mountain. A narrow path, no more than a foot or two wide, spiraled around the mountain to a glittering temple at the summit. The monk ascended at varying rates of speed, stopping many times along the way to rest and eat dried fruit he carried with him. He reached the temple shortly before sunset. After several days of fasting and meditation he began his journey back along the same path, starting at sunrise and again walking at variable speeds with many pauses along the way. His average speed descending was, of course, greater than his average climbing speed. Prove that there is a spot along the path that the monk will occupy on both trips at precisely the same time of day.

Popularity: 21% [?]

What is an Intermediate Certificate Authority (CA) and why do I need one? An Intermediate CA is an authority that you use to create your own SSL certificates in a PKI environment. An Intermediate CA depends on a Root CA that is the origin of the chain of trust. The idea is that if your Intermediate CA gets compromised or you decide to revocate all the certificates issued by it, you can still use your Root CA without further inconvenience for your users (the users only need to have installed the certificate of the Root CA in their browsers).

As for the second question, the sort answer is that chances are that you really do not need one but for the shake of the experiment lets get our hands dirty!
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Popularity: 100% [?]

This has not been the first time I have tried, but it has been the first time it has worked. And the best of it, no Partition Magic or (qt)parted is needed, just pure old tune2fs, resize2fs and fdisk (read the man pages and backup everything as usual ).
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Popularity: 40% [?]

Popularity: 12% [?]

Instructions follow on how to build and harden one of the most common configurations out there.
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Popularity: 19% [?]

Every now and then I need to send by email some file to a friend or coworker or even myself. I have found that the easiest way to do this is just having a shell script that do the hard work for you.

After some research I found a set of scripts that actually do what I want (credit goes to Heiner Steven). The bad news is that this is not a full-bash solution. The scripts use the metasend command to send files as MIME atachments.

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Popularity: 17% [?]

Here is a tiny script that can be usefull to terminate (kill -9) all the programs which contain a certain string (i.e.: kill all the running copies of ping).

#!/bin/bash

for foo in `ps aux | grep $1 | awk '{print $2}'`;  do kill -9 $foo; done

Just run: matar <program name> and that’s it. They are all gone.

Popularity: 16% [?]