Conclusion

Although our coverage of hardware has been sparse, this chapter has introduced the concept. We hope it will inspire you to perform your own research.

We have introduced the basic instructions needed to read from and write to hardware, and some of the "gotchas" to watch out for. Technical manuals are available that cover the bus in excruciating detail, and you should obtain one of these manuals if you want to explore the system.^[9] We hinted at the potential of hardware exploitation with BIOS modification and microcode updates. We illustrated a useful rootkit feature called keystroke monitoring. And, as always, we would like to drive home the point that it's possible to defeat most rootkit-detection schemes by simply getting as low as possible in the system.

^[9] See, for example, the "PC System Architecture Series" books, authored by Don Anderson and Tom Shanley (with others), published by Addison-Wesley.