Data integrity and host intrusion alert system

 Samhain is an integrity checker and host intrusion detection system that
 can be used on single hosts as well as large, UNIX-based networks.
 It supports central monitoring as well as powerful (and new) stealth
 features to run undetected on memory using steganography.
 .
 Main features
     * Complete integrity check
          + uses cryptographic checksums of files to detect
            modifications,
          + can find rogue SUID executables anywhere on disk, and
     * Centralized monitoring
          + native support for logging to a central server via encrypted
            and authenticated connections
     * Tamper resistance
          + database and configuration files can be signed
          + logfile entries and e-mail reports are signed
          + support for stealth operation