Hell Labs

Há algum tempo um banco passou a utilizar um sistema de verificação do computador do qual é realizado o acesso a seu sistema de internet banking, oferecendo suporte a diferentes sistemas operacionais incluindo Linux. O funcionamento desse sistema pode ser facilmente inferido com base nas chamadas feitas pela biblioteca de autenticação, dos símbolos públicos disponíveis e um pouco de dedução. O método utilizado é surpreendentemente simples tanto em conceito como em implementação; a descrição a seguir, obtida de uma breve análise das chamadas e símbolos disponíveis, pode ser de interesse dos usuários do sistema que desejem saber mais sobre os dados que são coletados de seus computadores.

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Slow booting plagues most Linux distributions today, and while this is not a such big issue for systems that are booted once a year, it becomes an annoyance in laptops or other computers you initialize every day. Different solutions for this problem have been proposed, but booting of a typical Linux system today still takes too much time. It has been said that the Asus Eeepc boots remarkably faster than regular Linux distributions, thanks to its “fastinit” system initialization program. A quick analysis of its workings shows what it essentally does, and it’s quite obvious: start the user interface as fast as possible, and initialize the rest later. A more detailed analysis allowed us to rewrite it, and even find a couple of bugs in the original code.

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Recent rediscovery of xmp and the amount of improvements on the player since then is proof that modplaying is still one of my obsessions favorite idle-time activities. Like coding, or reverse engineering file formats. Put them together, and what you get is a modplayer with support to strange file formats you possibly never heard of, such as STMIK (a precursor of Future Crew’s famous S3M format), MASI (used in some old DOS games such as Epic Pinball and Jazz Jackrabbit), DIGI Booster (Amiga), TCB Tracker (Atari) and so on. This time we had a different and intriguing challenge: a simple module format with a rather strange sound sample encoding. If you’re interested in retrocomputing, reverse engineering, investigative stories, or Python, read on.

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