AIDE (Advanced Intrusion Detection Environment) is a free
replacement for Tripwire. It does the same things as the
semi-free Tripwire and more.

There are other free replacements available so why build
a new one? All the other replacements do not achieve the
level of Tripwire. And I wanted a program that would exceed
the limitations of Tripwire.

What does it do?

It creates a database from the regular expression rules
that it finds from the config file. Once this database is
initialized it can be used to verify the integrity of the
files. It has several message digest algorithms (md5,sha1,
rmd160,tiger,haval,etc.) that are used to check the integrity
of the file. More algorithms can be added with relative ease.
All of the usual file attributes can also be checked for
inconsistencies. It can read databases from older or newer
versions. See the manual pages within the distribution
for further info.

The AIDE homepage is located at:

	http://www.cs.tut.fi/~rammer/aide.html