Jon's Post Categories: Computers

This category contains all the posts related to computers: programming, security, conferences, hardware, software, etc. Since computers are involved in probably everything that I do and have done since grade school, most of my news posts probably show up under this category.

 

Uh no! Gnome Failed
For a long while now, since Gnome3 (gnome shell) felt kinda stable, I've been using that as my main windowing environment on my Gentoo laptop for what feels like a decade now. Maybe not that long. Something that I don't think I've seen in a while, though I probably should have way more often is a notorious screen that comes up when something somwhere between the hardware, drivers, X, mutter, any number of applications and clients, gtk, maybe wayland, all the way to the gnome base, goes wrong and it gets trapped, the equivalent of the Windows BSOD appears.
11/13/2023

 

Postfix + Cyrus SASL + Authdaemond
Fixed the Postfix/SASL/Courier/Postgres setup I have on my new Gentoo server, wrote it down so 10 years from now if I wanted to do it again I'll know why it's not working.
2/1/2019

 

New Laptop Part 3

Several years ago, my last laptop upgrade was to the enormous Thinkpad W700. It was gigantic, heavy, and powerful, but the screen was big and the keyboard was big. These days, the quad core processor on the W700 just doesn't cut it, and the max of 8G of RAM was looking less and less adequate. It was time for an upgrade, and Lenovo stopped offering monster size laptops like the W700, so I had to go looking elsewhere for the upgrade. It had to have a pointing stick, a large keyboard, 17+ inch display with at least 1920x1080 resolution, be able to hold 32G of RAM, mulitple drive bays, along with the usual gamut of features, like the newest i7 processors. What I ended up with was an HP Zbook 17.

It was one of the only brands that had a pointing stick on a monster sized laptop, and it got mostly good reviews. Some other laptops that I looked into were Alienwares (no pointing stick), Dell Latitudes (screen size), Sager (no pointing stick, build quality), Acer Aspires (not monster enough, no pointing stick). Along with Alienware, I considered some of the other high-end gaming laptop manufacturers, but I was worried about build quality and service. Also, no pointing sticks. So the things that made me settle for the Zbook was the customizing, the customer service and warranty, the build quality, and the ability where I can return it if I didn't like it.

Click for the rest.
10/24/2014

 

Visualizing SASL/POP3/IMAP Automated Dictionary Attacks
I've been meaning to do this for a while now, but felt especially compelled because today happened to be a pretty heavy day of automated attacks on my mail servers SMTP(SASL)/POP3/IMAP services. So I have something that blocks these and those blocks are logged, and they go back to November of 2011. I know there's been a steady increase in the number of attacks over the years but I was also curious about what time most attacks happened and what days. So I wrote something to parse through all of these brute force dictionary attacks and do a per IP count of attacks. To clarify a little, these are connections to port 25, 110 or 143, at least 5 from a single IP over the course of a time window, that results in failed authentication attempts. 99% of the time, these are bogus users. So after gathering the data, I stuck them into a spreadsheet and (tried to) make some graphs.

First, let's look at the entire dataset, broken down by the number of attacks from unique IPs per day (click for entire image):

Click for the rest.
7/24/2014

 

Android Blood Alcohol Content Widget
Wrote my second Android app the other day. Sitting at the bar, I wondered silently to myself, "wouldn't it be nice to know what my BAC is right now, I could use it to determine all kinds of useful things like whether I should walk home or take a car service, or just call it a night". Not really doing any research, I decided to give it a shot this past weekend. Ended up there were a bunch of alcohol BAC calculators and a couple of them that were widgets. One of them looked really detailed with a ton of stats and features, but I really wanted something that was stupid simple; easy enough for someone who's hammered to use.

I've already went through 5 or 6 revisions, improving the UI a bit, adding customizable drinks, fixed some bugs, and optimized memory and CPU usage. You can see the app's page here, at the Google Play Store. Let me know if there's anything I can do to improve it or report any bugs if it doesn't work correctly.

10/11/2012

 

Summercon 2012


Here's a picture of Redpantz, one of the organizers, because I don't have a picture of myself.

Another successful year of Summercon in the books. This was the 2nd time we had Summercon at Littlefield in Brooklyn. I actually tried to take it a little easier this year, don't know how successful that was, but mainly because this year I won't be only 2 blocks away from the venue but a 30 minute walk. On Thursday when Redpantz and Jimbo arrived, we started drinking at lunch and had a rough time walking that far. Lots of cool talks this year, and 2 tools were released shortly after they were presented at the con (the IDA Toolbag and Vivisect version of Vtrace).

The schedule this year was a little more hangover friendly, doors didn't open until noon and talks not until 12:30 or so (though we were probably behind schedule on both counts). This meant that I didn't have to wake up super early and help run the registration tables, which was probably a bit more important this year than the last few years because there was a LOT of pre-registration and a surge was expected at the beginning. Fortunately, the registration desk ran pretty smoothly, thanks to the work of Michelle, Joann and Jimbo.

Click for the rest.

6/10/2012

 

Stop SOPA Protest
I took tesuji.org down for 24 hours and replaced everything, including any images served, with this page/image to take part in the protest against the Stop Online Piracy Act. Instead of being weaksauce about it and put up some javascript over the usual content and display an overlay to cover it up, I used Apache's mod_rewrite to internally redirect every request and serve only the Stop SOPA page or image (if an image was requested). Everything's back to normal now but I thought I'd put up a page of links about it.

Click for the rest.

1/19/2012

 

My URL Shortener
One of the projects that I've been working on recently involved coming up with a multi-purpose URL shortener, like bit.ly's or tinyurl's. I had put a good bit of thought into it but I haven't gotten around to actually implementing it for the project yet. I know the concept is sound and lots of other people use it, so it ultimately comes down to how short and is it long enough to cover (and some) what you plan on using it for.

So I get kind of bored and decided I'll implement a command-line url shortener that ties into my website (tesuji.org) and give it a whirl. I opted to be ghetto-extreme and use, not 3, but only 2 characters in my shortened URL. I can shorten anything that I want, like http://tesuji.org/qy or http://tesuji.org/LN. I'm using the unreserved and sub-delimiter characters from RFC-3986 (well, most of them) since in a shortener context, at least in mine, most of those sub-delimiters are useless.

Click for the rest.

8/16/2011

 

My first Android Live Wallpaper
6/19/2011

 

Summercon 2011
6/13/2011

 

Firefox and CTRL+Q
1/24/2011

 

libMatroska and Mplayer
10/29/2010

 

New Laptop! PART 2
9/10/2009

 

Linux, EDID, and the Nvidia->HDMI->Samsung HDTV

4/7/2009

 

Metacity is Lame (2007)

 

Summercon 2008

 

Automated Torrent Downloader for Tokyo Toshokan

 

Fractals and Electropaint, on youtube

 

Summercon 2007 (August 19, 2007)

 

Fractals (2007)

 

New Laptop! (June 11, 2006)

 

Begin Linux Certified laptop rant (December 20, 2005)

 

SMTP Honeypot (2005)

 

SSH Brute Force Attacks (August 31, 2005)

 

Lazy (March 10, 2004)

 

Mail Reader Update (2004)

 

Monopoly (2004)
Slightly inebriated one night at Mark and Mel's back porch, our conversation swayed to the topic of the old board game Monopoly. It was theorized that night, that certain spaces on the board had a statistically higher chance of being landed on than others. This, of course, begs the question whether every space had a fixed probability of being landed on. A brute force calculation of this lead to a very, very large factor of branching, and the conversation quickly moved on to other things. So I am at home one evening and decided to try and figure this out, not by writing a program to do all the branching (this is especially hard because of the Chance and Community Chest cards), but by writing a simulation of a game of Monopoly. This simulation is simple: one person playing monopoly, takes turns, rolls dice, moves spaces. The spaces that are landed on are recorded. Chance and Community Chest cards are accounted for in the movement. The results are far too long to put here, so I've put them HERE.

 

No More CTWM (2004)

 

Mail Reader Update (2003)

 

Filing Technique (2003)

 

Mail Reader Update (2003)

 

Summercon 2003 (June 9, 2003)

 

Mail Reader (April 9, 2002)

 

Mandelbrot Generator (2001)

 

Jerminal (1999)

 

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