Wolfgang S. Rupprecht wrote:
The core problem is to prevent someone from guessing users' passwords. You aren't going to achieve real security by hiding this or that attribute. If you don't want to worry about your users chosing bad non-random passwords, don't let them. Force them to use a 1k-2k RSA key for ssh and turn off all login types in sshd_config other than RSA2. That way any attacker has to correctly guess a 1k-bit computer generated number. That will almost certainly be much more secure than any password users will chose. Then you can look at the ssh log files and laugh. The universe isn't going to last long enough for them to guess even a small fraction of the keys.
Unless someone builds a quantum computer that can implement the Shor algorithm for nontrivial cases :-)