Don't underestimate the 'Home Computer Programmer'

The ingenuity of the home programmer is baffling writes Duncan Davidson.

Last night, I met up with a couple of friends. After talking for a while, I pulled on a flame thrower and went looking for trouble. Within a couple of minutes I’d incinerated a bunch of guys sat in a jeep, and moved on somewhere else with my ‘crew’ in tow, fanned-out in a line army style.

In case you aren’t quite with me, I was playing an online computer game – and all of my victims will live to fight another day (or until tonight anyway). The game in question (PC Halo, very popular with Serio staffers) is one that allows you to work with other players as a team, talk to them, and devise plans and strategies together. Although the media image is of the solitary gamer, modern games allow communication and interaction between real people in a way scarcely imaginable 10 years ago. My crew includes a leading Veterinary researcher, a Serio colleague, a toolshop owner, a computer programmer (me) and a Danish construction worker.

As we moved off to engage the enemy across a barren landscape, we were all picked off by single shots to the head from great distance – something that requires great skill to do.

Closer inspection revealed that our assailant was using what is called an aimbot – an aiming robot – that can be used with devastating results. Removing any elements of skill and spoiling the experience for the legitimate gamer, aimbots infect online gaming, defying efforts by companies such as Valve and others to stamp them out.

Unusually, the source code for the Halo aimbot is available online, although I’ll provide no link to it. Examining this code has taught me never to underestimate the skills of the teenage code bodger - the ingenuity shown is simply baffling.

The aimbot’s author had de-compiled the Halo game executable. I’ll explain what this means. Programmers like me use programming languages like C, C# and Delphi to write programs. These languages are human readable, use words like ‘if…’, ‘for..’ and so on. These statements (which run into many thousands of pages) are then transformed into machine code, which the computer executes. This stuff runs into millions of pages of numbers, and is unreadable to humans… or so I though.

The aimbot author had managed to work out where the game’s authors stored the position of each player. Think about that for a second. With millions of bytes, millions of numbers, he had somehow discovered the array in memory that contained all of the player details. What’s more, for each player, he had discovered what the player data meant – so he knew what direction you were facing, what your speed was…and he know how to access this from another process under Windows – no mean feat.

Computer games like Halo suffer from ‘lag’ caused by network latency – where you ‘see’ something is where it was a fraction of a second ago. To counter this, the aimbot has a system that looks at each player’s network performance and direction of travel and automatically adjusts the aim accordingly – with the impressive results I described at the start of this post.

The author of this software was, apparently, spurred by a comment from the game authors Bungie (now owned by Microsoft) that an ‘auto aiming cheat was impossible’. As I know I’m going to get hammered again tonight by this device, I wish he’d kept his mouth shut.