dos

42 Articles

BASH Games

February 5, 2013 by 18 Comments

Get serious about your shell scripting skills and maybe you can pull this one off. It’s a game of snake played in a BASH shell. It seems like a coding nightmare, but the final product turns out to be organized well enough for us to understand and took less than 250 lines of code.

[Martin Bruchanov] started on the project after pining for an old DOS game called Housenka. It’s another version of the classic Snake game which we’ve coded ourselves and seen in several projects including this head-to-head version using musical recorders as controllers. When using a terminal emulator capable of ANSI sequences the game is displayed in color using extended characters.

We give [Martin] bonus points for the way he wrote about his project. It describes the mechanics most would be interested in, like how the user input is captured and what drives the update function and food generation. The rest of the details can be gleaned by reading through the code itself.

Hacking A Parallel Port Flash Memory Programmer

July 14, 2012 by 12 Comments

[Pulko Mandy] doesn’t use his flash ROM programmer very often, but he does use it. When he tried to get support for a new chip and the manufacturer suggested he just buy a newer version he decided to hack the programmer and it’s software instead.

This device connects to the parallel port and was intended for use with MS-DOS systems (no wonder there’s no longer support from the company). The board uses logic chips to add read and write function. So the first step was to analyze how they connect together and come up with a set of commands. While at it he also made some changes to the board to bring the voltage more in spec and ensure the logic levels on the parallel port met the correct voltages.

His plan was to use the board with a Linux system so the parallel port interface can stay. He used what he learned from the hardware inspection to write his own interface in C++. It works with a chip he was able to use under the MS-DOS software, but he hasn’t gotten it to work with the chip that sparked this adventure. If you’re familiar with how the AT29C040A works please consider lending a hand.

XT IDE Controller

July 31, 2010 by 35 Comments

[Geordy] wanted to use some IDE devices but he didn’t have an interface card for his XT system, which can’t handle 16-bit  IDE. He looked around for 8-bit ISA controllers but they were hard to find and quite expensive. Lucky for him there’s an open source project that makes a solution to this problem. The XTIDE project brought together a group of vintage computing enthusiasts to design this ISA card. [Geordy] was even able to order a professional PCB from one of the forum members. He ordered the parts an soldered it together, costing about $30 total. He had a friend help him burn the code to the EEPROM but that’s easy enough to do with an Arduino, Bus Pirate, or one of several other methods. Now his grand plans at installing DOS 6.22 have been realized.

DIY Picture Frame Better Than Store Bought

July 30, 2010 by 22 Comments

[Daniel’s] homemade digital picture frame looks great, it’s well-built, and it has a nice set of features. It’s not made from a broken laptop and he didn’t build it around a microcontroller. Instead, he saved a 19″ LCD monitor with a burnt out back light caused by the extremely common blown capacitor problem. Twenty dollars on eBay landed him a small industrial single board computer to drive the system.

The software end of things is a curious conglomeration but considering the hardware constraints [Daniel] made some great choices. He’s using MS-DOS along with LxPic for slide shows and Mplayer for video. The rest of the software gets him up on the home network and enables IR remote control via LIRC. All o this makes for a beautiful product (video after the break includes some Doom footage) and the package is pulling just 40W when in use.

Slowloris HTTP Denial Of Service

June 17, 2009 by 40 Comments

[RSnake] has developed a denial of service technique that can take down servers more effectively. Traditionally, performing a denial of service attack entailed sending thousands of requests to a server, these requests needlessly tie up resources until the server fails. This repetitive attack requires the requests to happen in quick succession, and is usually a distributed effort. However, [RSnake]’s new technique has a client open several HTTP sessions and keeps them open for as long as possible. Most servers are configured to handle only a set number of connections; the infinite sessions prevent legitimate requests from being handled, shutting down the site. This vulnerability is present on webservers that use threading, such as Apache.

A positive side effect of the hack is that the server does not crash, only the HTTP server is affected. His example perl implementation, slowloris, is able to take down an average website using only one computer. Once the attack stops, the website will come back online immediately.

Update: Reader [Motoma] sent in a python implementation of slowloris called pyloris

[photo: cutebreak]

Russia Vs Georgia, The Online Front

August 13, 2008 by 19 Comments


While we’re sure that just about everyone has heard about the conflict between Russia and Georgia, few have probably heard about the role of cyber attacks in the conflict. Shortly before Russia’s armed response, Georgian state web servers were attacked by individuals assumed to be Russian hackers. This attack almost completely obliterated Georgia’s online presence by shutting down the website for the Ministry of Defense, and the Central Government’s main site. The Russian attackers seem to be using some form of sustained DDoS to keep many Georgian sites offline. In an effort to preserve some web presence, the Georgian Government transferred [President Mikheil Saakashvili]’s site to a US hosting provider in Atlanta. The Ministry of Foreign Affairs even created a BlogSpot page after their website initially went down. While politically motivated DDoS attacks have not been rare in past months, this seems to be the first time where the attacking party can be clearly identified. This seems to be the start of a trend where the unconventional methods of cyber warfare are used to gain an advantage over the enemy.

[photo: somefool]