Random password generation

[Sean Murphy]

When creating user accounts with adduser you can have the system 
generate a random password.

Can you use a tool included in FreeBSD to change specific existing users 
passwords with a random one such as the one in adduser?

it would also be usefull to do this from a input file to do multiple users.

The passwords I would need on the screen to give to the users.

If not is there an open source one to do this?