Building Secure Servers with Linux

Using Tripwire

Among the most celebrated and useful things to come out of Purdue’s COAST project (http://www.cerias.purdue.edu/coast/) was the Unix integrity checker Tripwire, created by Dr. Eugene Spafford and Gene Kim. Tripwire was originally both open source and free, but in 1997, Tripwire went commercial, and fee-free use was restricted to academic and other noncommercial settings.

Happily, a couple of years ago, Tripwire, Inc. released “Tripwire Open Source, Linux Edition.” Until Tripwire Open Source was released, the older Academic Source Release (ASR) lacked features long available in commercial versions of Tripwire. But Tripwire Open Source is a more-or-less current version of the commercial product. Although it still lacks a few “enterprise” features such as centralized management of multiple systems (Tripwire, Inc. understandably still wishes to differentiate its commercial product line), it is functionally very similar to the commercial Tripwire for Servers.

Note that Tripwire Open Source is free for use only on noncommercial Unices (i.e., Linux and Free/Net/OpenBSD). In fact, it’s officially supported only on Red Hat Linux and FreeBSD, although there’s no obvious reason why it shouldn’t compile and run equally well on other Linux and BSD distributions. (I run it not only on Red Hat, but also on SuSE and Debian Linux, with no problems to report). For commercial Unices such as Sun Solaris and HP-UX, commercial Tripwire is still the only legal option in commercial settings. ...