Shows SSH hostkeys. Shows the target SSH server's key fingerprint and (with high enough verbosity level) the public key itself. It records the discovered host keys in 'nmap.registry' for use by other scripts. Output can be controlled with the 'ssh_hostkey' script argument. The script also includes a postrule that check for duplicate hosts using the gathered keys. SYNTAX: ssh_hostkey: Controls the output format of keys. Multiple values may be given, separated by spaces. Possible values are - ''full'': The entire key, not just the fingerprint. - ''bubble'': Bubble Babble output, - ''visual'': Visual ASCII art representation. - ''all'': All of the above.