DOM is a proof of concept implementing a solution similar to fail2ban. It parses Suricata EVE log file searching for SSH event. If the client version is based on libssh, it adds the host to a blacklist by using ipset.

Go into the source directory and run:

./dom -f /usr/local/var/log/suricata/eve.json

Full options are available via '-h' option:

usage: dom [-h] [-f FILE] [-s IPSET] [-v] [-l LOG] [-m MOTIF] [-i] [-D]

Deny On Monitoring

optional arguments:
  -h, --help            show this help message and exit
  -f FILE, --file FILE  JSON file to monitor
  -s IPSET, --ipset IPSET
                        Set IPSET for blacklist
  -v, --verbose         Show verbose output, use multiple times increase
                        verbosity
  -l LOG, --log LOG     File to log output to (default to stdout)
  -m MOTIF, --motif MOTIF
                        String to look for in event
  -i, --invert          Invert match: trigger action if not found
  -D, --daemon          Run as unix daemon

If you know that regular client are using a software client (like OpenSSH) then you can use motif and invert options to trigger an action on all clients not using this software:

./dom -f /usr/local/var/log/suricata/eve.json -i -m OpenSSH